SuSE 10.1 is very buggy. I can't wait to ditch it. So, one solution is get your data off to safe alternate location and ugrade to SuSE 10.2 which is apparently better. A newer or another distro will simply install over your SuSE distro without disturbing other OSes you have on the drive. You could get your data off with any of the live CDs (e.g., Knoppix, Ubuntu) and either a network share, USB drive or even CD-R or DVD-R.
A more Linux-like thing to do would be to try to fix the problem: Think of what you have done recently on the computer. Have you made any changes in SuSE itself or from your other OS (Windows?) which might have caused this? Upgrades? Configuration changes? Hardware changes? Turned services on or off?
I would also try booting in "safe mode" or single-user mode; alternately, try booting without splash screen to see if you can see terminal-style output during the boot up. If you can boot into single-user/"safe" mode look at output from 'dmesg' and 'cat /var/log/messages'. If you can't boot up even in safe mode, try booting with a live CD and copying the /var/log/messages file off for analysis.
If you can come back with some answers to the above question and output from the messages log or dmesg, I'll try to help you.