BEFORE ANYTHING
This is not for begginers!!! follow up if you know exactly what you are doing.
GO TO WORK
A. LIBC6
1. Get following files or equivalent:

belocs-locales-bin_2.3.5-5ubuntu7_i386.deb
libc6_2.3.6-0ubuntu20_i386.deb
locales_2.3.18_all.deb
2. Force installation:
# dpkg --force-all -i locales_2.3.18_all.deb
yes that finish with a lot of errors, then:
# dpkg --force-all -i belocs-locales-bin_2.3.5-5ubuntu7_i386.deb
again with errors, now to fix all:
# dpkg -i libc6_2.3.6-0ubuntu20_i386.deb
3. Getting new sources.list
deb http://archive.ubuntu.com/ubuntu/ dapper main restricted
deb-src http://archive.ubuntu.com/ubuntu/ dapper main restricted
deb http://archive.ubuntu.com/ubuntu/ dapper-updates main restricted
deb-src http://archive.ubuntu.com/ubuntu/ dapper-updates main restricted
deb http://archive.ubuntu.com/ubuntu/ dapper universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ dapper universe multiverse
deb http://archive.ubuntu.com/ubuntu/ dapper-backports main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ dapper-backports main restricted universe multiverse
deb http://security.ubuntu.com/ubuntu dapper-security main restricted
deb-src http://security.ubuntu.com/ubuntu dapper-security main restricted
deb http://security.ubuntu.com/ubuntu dapper-security universe multiverse
deb-src http://security.ubuntu.com/ubuntu dapper-security universe multiverse
Of course:
# apt-get update
Yes some errors related to GPG. Follow only.
4. Purging a little
# dpkg -P tzdata apt-utils dselect
Oh! no errors!
B. SYSV
1. Get following files or equivalent:

sysv-rc_2.86.ds1-6ubuntu32_all.deb
initscripts_2.86.ds1-6ubuntu32_i386.deb
sysvinit_2.86.ds1-6ubuntu32_i386.deb
lsb-base_3.1-5ubuntu2_all.deb
util-linux_2.12r-4ubuntu6_i386.deb
gcc-4.0-base_4.0.3-1ubuntu5_i386.deb
apt_0.6.43.3ubuntu2_i386.deb
libgcc1_4.0.3-1ubuntu5_i386.deb
libstdc++6_4.0.3-1ubuntu5_i386.deb
libcap1_1.10-14_i386.deb
libdb4.3_4.3.29-5build1_i386.deb
libpam-foreground_0.3_i386.deb
libpam-runtime_0.79-3ubuntu14_all.deb
libpam0g_0.79-3ubuntu14_i386.deb
libsepol1_1.10-1_i386.deb
libselinux1_1.28-2ubuntu2_i386.deb
bash_3.1-2ubuntu10_i386.deb
libpam-modules_0.79-3ubuntu14_i386.deb
base-passwd_3.5.11_i386.deb
original-awk_2005-04-24-1_i386.deb
base-files_3.1.9ubuntu7_i386.deb
libattr1_2.4.25-1_i386.deb
libacl1_2.2.34-1ubuntu1_i386.deb
coreutils_5.93-5ubuntu4_i386.deb
debianutils_2.15.2_i386.deb
libncurses5_5.5-1ubuntu3_i386.deb
dpkg_1.13.11ubuntu6_i386.deb
adduser_3.80ubuntu2_all.deb
cron_3.0pl1-92ubuntu1_i386.deb
debconf_1.4.72ubuntu9_all.deb
debconf-i18n_1.4.72ubuntu9_all.deb
e2fslibs_1.38-2ubuntu2_i386.deb
ifupdown_0.6.7ubuntu7_i386.deb
iputils-ping_20020927-3ubuntu1_i386.deb
libcomerr2_1.38-2ubuntu2_i386.deb
liblocale-gettext-perl_1.05-1_i386.deb
libpopt0_1.7-5_i386.deb
libslang2_2.0.5-1build2_i386.deb
libss2_1.38-2ubuntu2_i386.deb
libtext-charwidth-perl_0.04-3_i386.deb
libtext-iconv-perl_1.4-2_i386.deb
libtext-wrapi18n-perl_0.06-4_all.deb
libuuid1_1.38-2ubuntu2_i386.deb
libwrap0_7.6.dbs-8ubuntu1_i386.deb
login_4.0.13-7ubuntu3.2_i386.deb
logrotate_3.7.1-2_i386.deb
lsb-base_3.1-5ubuntu2_all.deb
module-init-tools_3.2.2-1ubuntu7_i386.deb
ncurses-bin_5.5-1ubuntu3_i386.deb
netbase_4.24ubuntu3_all.deb
net-tools_1.60-16ubuntu2_i386.deb
passwd_4.0.13-7ubuntu3.2_i386.deb
perl-base_5.8.7-10ubuntu1_i386.deb
sed_4.1.4-5_i386.deb
tcpd_7.6.dbs-8ubuntu1_i386.deb
util-linux_2.12r-4ubuntu6_i386.deb
zlib1g_1.2.3-6ubuntu4_i386.deb
e2fsprogs_1.38-2ubuntu2_i386.deb
libblkid1_1.38-2ubuntu2_i386.deb
klogd_1.4.1-17ubuntu7_i386.deb
sysklogd_1.4.1-17ubuntu7_i386.deb
busybox-initramfs_1.01-4ubuntu3_i386.deb
grepmap_1.1.0-1_i386.deb
klibc-utils_1.1.16-1ubuntu5_i386.deb
cpio_2.6-10_i386.deb
initramfs-tools_0.40ubuntu32_all.deb
libklibc_1.1.16-1ubuntu5_i386.deb
udev_079-0ubuntu34_i386.deb
libgdbm3_1.8.3-2_i386.deb
perl-modules_5.8.7-10ubuntu1_all.deb
perl_5.8.7-10ubuntu1_i386.deb
perl-base_5.8.7-10ubuntu1_i386.deb
binutils_2.16.1cvs20060117-1ubuntu2.1_i386.deb
dash_0.5.3-1ubuntu1_i386.deb
cramfsprogs_1.1-6_i386.deb
initrd-tools_0.1.84ubuntu1_all.deb
dbus_0.60-6ubuntu8_i386.deb
libdbus-1-2_0.60-6ubuntu8_i386.deb
libxau6_1.0.0-0ubuntu4_i386.deb
dmidecode_2.7-3_i386.deb
libice6_1.0.0-0ubuntu2_i386.deb
laptop-detect_0.12.1-ubuntu2_i386.deb
libsm6_1.0.0-0ubuntu2_i386.deb
x11-common_7.0.0-0ubuntu45_i386.deb
libncursesw5_5.5-1ubuntu3_i386.deb
dialog_1.0-20060101-1_i386.deb
libexpat1_1.95.8-3_i386.deb
cpp_4.0.3-1_i386.deb
cpp-4.0_4.0.3-1ubuntu5_i386.deb
libx11-6_1.0.0-0ubuntu9_i386.deb
gettext_0.14.5-2ubuntu3_i386.deb
intltool-debian_0.34.1+20050828ubuntu1_all.deb
gettext-base_0.14.5-2ubuntu3_i386.deb
grep_2.5.1.ds2-4_i386.deb
findutils_4.2.27-1ubuntu1_i386.deb
2. pacific installation:
# dpkg -i sysv-rc_2.86.ds1-6ubuntu32_all.deb
# dpkg -i initscripts_2.86.ds1-6ubuntu32_i386.deb
# dpkg -i sysvinit_2.86.ds1-6ubuntu32_i386.deb
# dpkg -i lsb-base_3.1-5ubuntu2_all.deb
# dpkg -i util-linux_2.12r-4ubuntu6_i386.deb
# dpkg -i gcc-4.0-base_4.0.3-1ubuntu5_i386.deb
# dpkg -i apt_0.6.43.3ubuntu2_i386.deb
# dpkg -i libgcc1_4.0.3-1ubuntu5_i386.deb
# dpkg -i libstdc++6_4.0.3-1ubuntu5_i386.deb
# dpkg -i libcap1_1.10-14_i386.deb
# dpkg -i libdb4.3_4.3.29-5build1_i386.deb
# dpkg -i libpam-foreground_0.3_i386.deb
# dpkg -i libpam-runtime_0.79-3ubuntu14_all.deb
# dpkg -i libpam0g_0.79-3ubuntu14_i386.deb
# dpkg -i libpam-modules_0.79-3ubuntu14_i386.deb
# dpkg -i libsepol1_1.10-1_i386.deb
# dpkg -i libselinux1_1.28-2ubuntu2_i386.deb
# dpkg -i base-passwd_3.5.11_i386.deb
# dpkg -i original-awk_2005-04-24-1_i386.deb
# dpkg -i base-files_3.1.9ubuntu7_i386.deb
# dpkg -i libattr1_2.4.25-1_i386.deb
# dpkg -i libacl1_2.2.34-1ubuntu1_i386.deb
# dpkg -i coreutils_5.93-5ubuntu4_i386.deb
# dpkg --force-all -i debianutils_2.15.2_i386.deb
# dpkg -i libncurses5_5.5-1ubuntu3_i386.deb
# dpkg -i bash_3.1-2ubuntu10_i386.deb
# dpkg -i dpkg_1.13.11ubuntu6_i386.deb
# dpkg -i adduser_3.80ubuntu2_all.deb
# dpkg -i cron_3.0pl1-92ubuntu1_i386.deb
# dpkg -i debconf_1.4.72ubuntu9_all.deb
# dpkg -i debconf-i18n_1.4.72ubuntu9_all.deb
# dpkg -i e2fslibs_1.38-2ubuntu2_i386.deb
# dpkg -i ifupdown_0.6.7ubuntu7_i386.deb
# dpkg -i iputils-ping_20020927-3ubuntu1_i386.deb
# dpkg -i libcomerr2_1.38-2ubuntu2_i386.deb
# dpkg -i liblocale-gettext-perl_1.05-1_i386.deb
# dpkg -i libpopt0_1.7-5_i386.deb
# dpkg -i libslang2_2.0.5-1build2_i386.deb
# dpkg -i libss2_1.38-2ubuntu2_i386.deb
# dpkg -i libtext-charwidth-perl_0.04-3_i386.deb
# dpkg -i libtext-iconv-perl_1.4-2_i386.deb
# dpkg -i libtext-wrapi18n-perl_0.06-4_all.deb
# dpkg -i libuuid1_1.38-2ubuntu2_i386.deb
# dpkg -i libwrap0_7.6.dbs-8ubuntu1_i386.deb
# dpkg -i login_4.0.13-7ubuntu3.2_i386.deb
# dpkg -i logrotate_3.7.1-2_i386.deb
# dpkg -i lsb-base_3.1-5ubuntu2_all.deb
# dpkg -i module-init-tools_3.2.2-1ubuntu7_i386.deb
# dpkg -i ncurses-bin_5.5-1ubuntu3_i386.deb
# dpkg -i netbase_4.24ubuntu3_all.deb
# dpkg -i net-tools_1.60-16ubuntu2_i386.deb
# dpkg -i passwd_4.0.13-7ubuntu3.2_i386.deb
# dpkg -i sed_4.1.4-5_i386.deb
# dpkg -i tcpd_7.6.dbs-8ubuntu1_i386.deb
# dpkg -i util-linux_2.12r-4ubuntu6_i386.deb
# dpkg -i zlib1g_1.2.3-6ubuntu4_i386.deb
# dpkg -i e2fsprogs_1.38-2ubuntu2_i386.deb
# dpkg -i libblkid1_1.38-2ubuntu2_i386.deb
# dpkg -i klogd_1.4.1-17ubuntu7_i386.deb sysklogd_1.4.1-17ubuntu7_i386.deb
# dpkg -i libgdbm3_1.8.3-2_i386.deb
# dpkg -i perl-modules_5.8.7-10ubuntu1_all.deb
# dpkg -i perl_5.8.7-10ubuntu1_i386.deb perl-base_5.8.7-10ubuntu1_i386.deb
# dpkg -i busybox-initramfs_1.01-4ubuntu3_i386.deb grepmap_1.1.0-1_i386.deb klibc-utils_1.1.16-1ubuntu5_i386.deb cpio_2.6-10_i386.deb initramfs-tools_0.40ubuntu32_all.deb libklibc_1.1.16-1ubuntu5_i386.deb udev_079-0ubuntu34_i386.deb
# dpkg -i binutils_2.16.1cvs20060117-1ubuntu2.1_i386.deb
# dpkg -i dash_0.5.3-1ubuntu1_i386.deb
# dpkg -i cramfsprogs_1.1-6_i386.deb
# dpkg -i initrd-tools_0.1.84ubuntu1_all.deb
# dpkg -i dbus_0.60-6ubuntu8_i386.deb libdbus-1-2_0.60-6ubuntu8_i386.deb libxau6_1.0.0-0ubuntu4_i386.deb dmidecode_2.7-3_i386.deb libice6_1.0.0-0ubuntu2_i386.deb laptop-detect_0.12.1-ubuntu2_i386.deb libsm6_1.0.0-0ubuntu2_i386.deb x11-common_7.0.0-0ubuntu45_i386.deb libexpat1_1.95.8-3_i386.deb
# dpkg --force-all -P libx11-data
# dpkg -i libx11-6_1.0.0-0ubuntu9_i386.deb
# dpkg -i libncursesw5_5.5-1ubuntu3_i386.deb dialog_1.0-20060101-1_i386.deb
# dpkg -i cpp_4.0.3-1_i386.deb cpp-4.0_4.0.3-1ubuntu5_i386.deb
# dpkg -i gettext_0.14.5-2ubuntu3_i386.deb intltool-debian_0.34.1+20050828ubuntu1_all.deb gettext-base_0.14.5-2ubuntu3_i386.deb
# dpkg -i grep_2.5.1.ds2-4_i386.deb findutils_4.2.27-1ubuntu1_i386.deb
3. Purging some packages
# dpkg -P base-config gcc-3.3 gcc-4.0 gcc debootstrap binutils dpkg-dev debhelper alien cupsys-bsd cupsys-client libdevmapper1.02
!! if some dependencies problem then purge all that dependencies. !!
C. Good by Debian (I miss you everyday)
1. Running Risks like a Crazy
# apt-get -f install
of course you could answer: Yes, as I say!
2. To Pray!!
the faith may everything. This is not a joke!
D. Hello Ubuntu
1. Updating all surviving packages
# apt-get dist-upgrade
2. Installing base packages
# apt-get install ubuntu-minimal
3. Getting New Kernel
# apt-get install linux-image-2.6.15-26-686 libc6-686
4. Reinstalling applications you need
# apt-get install everything you need

That's all.
God Bless You