Ram doesnt go bad. It either works or you get a blue screen of death with it doing physical memory dumps.... or kernel errors
Windows 98 and Windows ME both SUCK (read SUCK) they have wicked crappy swap files sizesf(too small).....
Assuming that you've defragged, updated your virii definitions, cleaned out any spyware, regularly... You can just make a simple edit, to increase your swap file size.
heres what you're lookin for
Threaded Mode