PPA Installation – Screen Turns Gray on Boot After Installing a PPA

Problem
I recently added ppa:eugenesan/ppa to my maverick installation to install smartgit. Right after apt-get listed a bunch of updates that I immediately installed. After rebooting I noticed that grub changed. The new version of grub is 1.99~rc1-2ubuntu1~eugenesan~maverick1. Booting up my system I had to admit that it no longer launches the login screen. It still shows the Ubuntu logo (new style also) but after that the screen turns gray.

Solution ideas
I already found the apt-get history under /var/log/apt/history.log and it lists all the software that came with the new repository. The list is huge.

Further, I read that ppa-purge can uninstall a repository and all its software. I am not sure if I understood right since it does not affect the grub version installed. That would be the easiest to see.

Can you help me to fix my system? I have access to the command line.

Vague solution steps
Thanks to Lekensteyn. In the meantime I read and tried what was written in the other thread. Nonetheless, I cannot uninstall the software version that came by eugenesan. This is what I tried:

sudo ppa-purge ppa:eugenesan/ppa
rm /etc/apt/sources.list.d/eugenesan...

Moreover, I found out that a "Previous Linux version" boots up normally. The default grub entries are Ubuntu, with Linux 2.6.35-31-generic and ..(recovery mode) – the couple that does not boot up.
But when I choose Ubuntu, with Linux 2.6.35-30-generic from the list, everything works fine. Do you understand what happens? Could it be that the graphic resolution is just set wrong OR do you think grub is the problem?

Installation log
To give a complete overview I got the history.log for apt-get. This is what happened in the meantime.

# ***** /var/log/apt/history.log *****

Start-Date: 2011-12-07  19:33:18
Commandline: apt-get install smartgit
Install: smartgit:amd64 (2.1.4-0~eugenesan~maverick9)
End-Date: 2011-12-07  19:33:36

Start-Date: 2011-12-07  19:50:00
Install:
libfile-desktopentry-perl:amd64 (0.04-2),
isc-dhcp-client:amd64 (4.1.1-P1-15ubuntu3.2~eugenesan~maverick1),
ttf-fixedsys-excelsior:amd64 (3.0-1ubuntu2~eugenesan~maverick2),
libfile-mimeinfo-perl:amd64 (0.15-1),
isc-dhcp-common:amd64 (4.1.1-P1-15ubuntu3.2~eugenesan~maverick1, automatic),
p7zip-full:amd64 (9.04~dfsg.1-1)


Upgrade:
meld:amd64 (1.3.2-1ubuntu1, 1.5.0-0ubuntu1~eugenesan~maverick1),
codeblocks:amd64 (10.05-0ubuntu1, 10.05-1~eugenesan~maverick1),
git-all:amd64 (1.7.7.2-1~ppa0~maverick1, 1.7.8-0ppa1~maverick1),
libglib2.0-data:amd64 (2.26.1-0ubuntu1, 2.28.0-0ubuntu1~eugenesan~maverick1),
git-daemon-run:amd64 (1.7.7.2-1~ppa0~maverick1, 1.7.8-0ppa1~maverick1),
network-manager-gnome:amd64 (0.8.1+git.20100809t190028.290dc70-0ubuntu3, 0.8.3+git.20110203t003354.9bf0b98-0ubuntu1~nmt1~maverick),
git-doc:amd64 (1.7.7.2-1~ppa0~maverick1, 1.7.8-0ppa1~maverick1),
git-cvs:amd64 (1.7.7.2-1~ppa0~maverick1, 1.7.8-0ppa1~maverick1),
git-gui:amd64 (1.7.7.2-1~ppa0~maverick1, 1.7.8-0ppa1~maverick1),
rubygems:amd64 (1.3.7-2, 1.5.3-0~eugenesan~maverick2),
libnm-util1:amd64 (0.8.1+git.20100810t184654.ab580f4-0ubuntu2, 0.8.3+git.20110201t160144.9b61ec7-0ubuntu1~nmt2~maverick),
git-man:amd64 (1.7.7.2-1~ppa0~maverick1, 1.7.8-0ppa1~maverick1),
screen:amd64 (4.0.3-14ubuntu4, 4.1.0git066b098-0~eugenesan~maverick3),
libpcre3:amd64 (8.02-1, 8.12-1~eugenesan~maverick1),
hotot:amd64 (0.9.7~git-1259-g63e05cf-0ubuntu0ppa1~maverick1, 0.9.7~git-1280-g9b00609-0ubuntu0ppa1~maverick1),
git-svn:amd64 (1.7.7.2-1~ppa0~maverick1, 1.7.8-0ppa1~maverick1),
libsoup-gnome2.4-1:amd64 (2.31.92-0ubuntu1.1, 2.32.2-2ub~eugenesan~maverick1),
grub-pc:amd64 (1.98+20100804-5ubuntu3.3, 1.99~rc1-2ubuntu1~eugenesan~maverick1),
libglib2.0-0:amd64 (2.26.1-0ubuntu1, 2.28.0-0ubuntu1~eugenesan~maverick1),
git-email:amd64 (1.7.7.2-1~ppa0~maverick1, 1.7.8-0ppa1~maverick1),
network-manager:amd64 (0.8.1+git.20100810t184654.ab580f4-0ubuntu2, 0.8.3+git.20110201t160144.9b61ec7-0ubuntu1~nmt2~maverick),
gitweb:amd64 (1.7.7.2-1~ppa0~maverick1, 1.7.8-0ppa1~maverick1),
git:amd64 (1.7.7.2-1~ppa0~maverick1, 1.7.8-0ppa1~maverick1),
libnm-glib2:amd64 (0.8.1+git.20100810t184654.ab580f4-0ubuntu2, 0.8.3+git.20110201t160144.9b61ec7-0ubuntu1~nmt2~maverick),
codeblocks-common:amd64 (10.05-0ubuntu1, 10.05-1~eugenesan~maverick1),
rdesktop:amd64 (1.6.0-3ubuntu2.1, 1.7.0-1ubuntu2~eugenesan~maverick1),
libglib2.0-bin:amd64 (2.26.1-0ubuntu1, 2.28.0-0ubuntu1~eugenesan~maverick1),
git-el:amd64 (1.7.7.2-1~ppa0~maverick1, 1.7.8-0ppa1~maverick1),
libglib2.0-dev:amd64 (2.26.1-0ubuntu1, 2.28.0-0ubuntu1~eugenesan~maverick1),
xdg-utils:amd64 (1.0.2+cvs20100307-1ubuntu0.3, 1.1.0~rc1-2~eugenesan~maverick1),
initramfs-tools:amd64 (0.98.1ubuntu6.1, 0.99ubuntu2.1~eugenesan~maverick1),
y-ppa-manager:amd64 (0.0.8.4-1~webupd8~maverick3, 0.0.8.5-1~webupd8~maverick),
codeblocks-contrib:amd64 (10.05-0ubuntu1, 10.05-1~eugenesan~maverick1),
git-arch:amd64 (1.7.7.2-1~ppa0~maverick1, 1.7.8-0ppa1~maverick1),
gitk:amd64 (1.7.7.2-1~ppa0~maverick1, 1.7.8-0ppa1~maverick1),
dhcp3-client:amd64 (3.1.3-2ubuntu6.3, 4.1.1-P1-15ubuntu3.2~eugenesan~maverick1),
libcodeblocks0:amd64 (10.05-0ubuntu1, 10.05-1~eugenesan~maverick1),
rubygems1.8:amd64 (1.3.7-2, 1.5.3-0~eugenesan~maverick2),
python-support:amd64 (1.0.9ubuntu1, 1.0.10ubuntu3~eugenesan~maverick1),
git-core:amd64 (1.7.7.2-1~ppa0~maverick1, 1.7.8-0ppa1~maverick1),
ttf-mscorefonts-installer:amd64 (3.2ubuntu2, 3.3ubuntu4~eugenesan~maverick4),
shutter:amd64 (0.88~ppa4~maverick1, 0.88.1~ppa3~maverick1),
handbrake-gtk:amd64 (4370svnppa1~maverick1, 4373svnppa1~maverick1),
python-gdata:amd64 (2.0.8-1.1, 2.0.13-1~eugenesan~maverick1),
grub-common:amd64 (1.98+20100804-5ubuntu3.3, 1.99~rc1-2ubuntu1~eugenesan~maverick1),
libjson-glib-1.0-0:amd64 (0.10.2-2ubuntu2.1, 0.12.2-0ubuntu1~eugenesan~maverick1),
libwxsmithlib0:amd64 (10.05-0ubuntu1, 10.05-1~eugenesan~maverick1),
ppa-purge:amd64 (0.2.8+bzr56~webupd8~maverick, 0.2.8+bzr59-0~61~maverick1),
initramfs-tools-bin:amd64 (0.98.1ubuntu6.1, 0.99ubuntu2.1~eugenesan~maverick1),
dhcp3-common:amd64 (3.1.3-2ubuntu6.3, 4.1.1-P1-15ubuntu3.2~eugenesan~maverick1),
libsoup2.4-1:amd64 (2.31.92-0ubuntu1.1, 2.32.2-2ub~eugenesan~maverick1)
Error: Sub-process /usr/bin/dpkg returned an error code (1)    
End-Date: 2011-12-07  20:03:24

Start-Date: 2011-12-08  11:31:33
Commandline: apt-get remove
Error: Sub-process /usr/bin/dpkg returned an error code (1)
End-Date: 2011-12-08  11:31:35

Start-Date: 2011-12-08  11:37:57
Commandline: apt-get install ppa-purge
Error: Sub-process /usr/bin/dpkg returned an error code (1)
End-Date: 2011-12-08  11:37:58

Start-Date: 2011-12-08  11:38:59
Commandline: apt-get remove rubygems1.8
Remove: 
rubygems:amd64 (1.5.3-0~eugenesan~maverick2), 
rubygems1.8:amd64 (1.5.3-0~eugenesan~maverick2)
End-Date: 2011-12-08  11:39:08

Start-Date: 2011-12-08  12:01:08
Commandline: apt-get purge screen
Purge: 
ubuntu-desktop:amd64 (1.207), 
byobu:amd64 (3.5-0ubuntu1.1), 
ubuntu-netbook:amd64 (2.035), 
screen:amd64 (4.1.0git066b098-0~eugenesan~maverick3)
End-Date: 2011-12-08  12:01:20

All entries from Start-Date: 2011-12-08 11:31:33 and later are already me trying to fix the system. There seems to be an error in the initial "eugenesan-installation"

Kernel under suspicion
Could it be that kernel 2.6.35-31 is not working on my machine? I cannot see an installation had happened in the history.log, though. In case I want to remove the kernel I found an article on how to remove a grub menu entry.