I installed iDeneb 1.3 and then 10.5.7 on my HP Compaq Mini 110 using the awesome guide from Version 2 - HP MINI OSX 10.5.7 Walkthrough

After completing the guide, I installed the video drivers from here to get quartz. Sleep, iSight, Quartz, Sound... All working, except the mic.

But then I decided to install two seemingly harmless updates: QuickTime and iTunes.
After the restart, the grey screen progress indicator thing will keep spinning forever.

I would never expect installing a few media players could mess up my system! (But it did)

-v shows that it freezes after:

MAC Framework successfully initialized
using 5242 buffer headers and 4096 cluster IO buffer headers

Note that -x doesn't even work

So my question is, what can I delete or move around in single user mode to get it working again?

Hmm this is kinda weird, try asking to nawcom on irc. go to irc.osx86.hu #hackint0sh if you get any useful info, please share it with the community.