I went to Crucial's site as I suggested you try above and got this message:
"No products are currently available for the system you selected. Your system may require proprietary or non-standard parts."
From the sounds of it, I wouldn't be surprised if you got the machine from someone who was going to throw it out. I would ask them if they still have memory for it lying around.
The fact that Crucial doesn't even carry memory for that model in stock is not a good sign. Any place you could find that did have compatible memory is likely to charge you quite a bit.
In other words, I wouldn't expect to do much with that machine. Certainly you could throw Windows 98 up to 2000 on it, but performance with XP might not be smooth.