How to debug a boot problem?

[Hartmut Niemann <Hartmut.Niemann@gmx.de>]

Hi!

I have debian testing on a SIS741 Athlon XP system,
Graphics is ATI 9250 (RV280) in case that gives a hint to somebody.

Kernel 2.6.30 runs fine.

Kernel 2.6.32 reaches 
       done.
        Setting parameters of disc: (none)
        Checking root file system...fsck from util-linux-ng 2.17.2
        Ursula-root: clean, ../.. files, ../.. blocks (I didn't write down the exact numbers)
        done.
and stops.

How do I find out, why boot stops here? Where does it stop? 
How can I find out what the next step which hangs the system is?
Could the new dependency based boot be the culprit?
Or the kernel based mode setting? 
As far as I remember both were new in this kernel?
What do you suggest to try next?

With best regards
Hartmut