iBook boots into BSD Prompt!

i was using Tiger on my ibook yesterday when Finder died, everything else was ok, nothing on the desktop and no spotlight, so i restarted (only the second time since installation in 4/29). To my suprise it booted into a Darwin/BSD prompt.
So I restarted. Same thing.
Restarted again. Same thing
I've tried booting into safe mode, single user mode, botting from Tiger DVD and reapiring permissions and selecting start up disk, but it keeps coming back!
I can log into the prompt from there, but i'm not too handy with Unix...any ideas on how I get OS X back?

I might try deleting all the widgets i had as a last attemt...