After automatic update only old kernel works.

Since I agreed to update Feisty with the latest updates it will not boot anymore. If I reach the desktop it flickers away and then I see a lot of text showing which modules are loaded, the last being "Running local boot scripts (/etc/rc.local)"

I'm a complete newbie so it is more than possible that I've just messed something up.

I saw some earlier bugs concerning "xorg-server-core 1:1.0.2-0ubuntu10.3" (https://launchpad.net/ubuntu/+source/xorg-server/+bug/57153)
that looked a bit like my problem but since I've got a newer xorg-version that shouldn't be the case, should it?
After running:
sudo aptitude show xserver-xorg-core | grep Version
I get:
Version: 2:1.2.0-3ubuntu3

I've got a Nvidia GeForce Go 6600 that I can't configure with Envy.

ProblemType: Crash
Architecture: i386
CrashCounter: 1
Date: Fri Mar 16 10:23:59 2007
Disassembly: 0xb7d4197f:
DistroRelease: Ubuntu 7.04
ExecutablePath: /usr/bin/Xorg
Package: xserver-xorg-core 2:1.2.0-3ubuntu3 [modified: usr/lib/xorg/modules/extensions/libglx.so]
PackageArchitecture: i386
ProcCmdline: /usr/X11R6/bin/X :0 -br -audit 0 -auth /var/lib/gdm/:0.Xauth -nolisten tcp vt7
ProcCwd: /etc/X11
ProcEnviron:
 LANGUAGE=
 PATH=/sbin:/bin:/usr/sbin:/usr/bin
 LANG=sv_SE.UTF-8
Signal: 11
SourcePackage: xorg-server
Stacktrace: #0 0xb7d4197f in ?? ()
StacktraceTop: ?? ()
ThreadStacktrace:

Uname: Linux petter-laptop 2.6.17-10-generic #2 SMP Tue Dec 5 22:28:26 UTC 2006 i686 GNU/Linux
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