Can't get anything to work

I have been unable to start Windows 98 at all in normal mode and have only been able to get it to load up fully in Safe Mode once or twice. Occasionally it scans the drive, but that never helps; it doesn't end up loading Windows anyway. When I was able to load Safe Mode I went to help and followed its instructions to run msconfig and do some sort of "diagnostic start-up." It told me to do a step-by-step confirmation, which I did, following the instructions to the letter, but after one of the prompts it just locked up and stopped doing anything. At this point I'm just going around in circles as nothing seems to be working. It locks up on normal mode and safe mode, and I don't see how any of the other options would do anything.

This problem arose when my father was scanning some pictures into the computer - it was taking a long time, and it finally locked up, I suppose.

My computer is custom-built by Proteva, 450 Pentium III, 192 MB RAM, 12 MB ATI video card (can't remember the exact name), Windows 98.

Thanks for any help.