Hmmm....Well first of all, as per everybodies advice, I wouldn't advise using Win98 now..too many security holes and not alot of support from MicroShaft.
You can't downgrade your installation of XP, unless you upgraded from Win98 and kept the FAT32 file system and kept the un-install files. Even if you have it's still very tricky, tried it once when I was first playing with XP..needless to say I gave up and did a clean install of XP....
More memory would be very good idea, 256mB is really the minimum you should run XP on, is your 256 in one stick or two? If it's in two make sure you've got them in the right slots to 'pair the memory up' (read mobo instuctions). If you've got a single stick of 256mB DDR, thats not a good way to run the system anyway, should always run DDR in pairs, so get yourself another stick of 256.
Right, next thing to look at is what do you have running in the background? What A/V are you running? Have you done a spy sweep with more than one proggy (I always use two)?
You could have a look at your start-up list (start, run, msconfig) and see if you've got stuff loading you no longer use or don't use often, just untick the box next to the line, most entries make sense, but if your not sure leave them alone, or look them up in google....
Have fun, let us know how you get on...
Phew!!! my fingers hurt now..-)lol :Cheers: