If this is a new problem try a System Restore to a point prior to the problem:
start > All Programs > Accessories > System Tools > System Restore
Also you might want to read this post and follow the instructions:
http://www.d-a-l.com/help/showthread.php?t=32403
It might be useful to post a log in that section of the forum.
After this issue is cleared up you should go to Windows Update and install SP2 and all subsequent Critical Updates.
Also running XP with only 128MB RAM is very problematic. You should have at least 256MB if not 512MB.