Honestly it would depend on what I would be doing with the computer. If it were to extend the life of the computer, I would go with a seriously nLite version of XP and that would allow me to run newer apps on it. I would possibly maybe upgrade the ram a bit more for XP to run better. I have an old P3 500 that runs a non-nLited XP and it works like a charm. I bet if I upgraded the ram to 512 it would get a huge boost in performance...and another jump would be if I upgraded the hard drive as well. I bet that is a rather large bottleneck right there. Amazing how fast the P3 really is despite being so old!