I'd go with 2000. In fact I did. I had 2000, upgraded to XP, then went back to 2000. XP itself is more weighty than 2000 memory/disc wise. The main thing I hate about it is the registration. If you change the hardware under XP you have to go through the whole registration thing again. Also my own experience is that 2000 was more stable than XP, however it's a few XP service paks later so I'd imagine XP is pretty stable right now. Basically XP was a waste of time and money for me. Unzipped