Technically speaking this would be illegal.
Microsoft claims that the license is non transferrable and not resellable - it's bound to the computer you've got it with (The XP
Pro version). Worse even - once you sell the computer the buyer loses all rights to using the operating system (even if you bundle it with the computer it originally came with). Microsoft claims that the new owner must acquire a new license. Go figure.
Stability of XP
? Well. YMMV.
Pro SP1 on P4-1.8 (@2.08GHz), 512MB, GA
-8IEXP motherboard, R8500 video card - no crashes yet, XP
installed in October 2003.
Pro SP1 on Athlon XP2500+ (o/c to 11*183MHz), 768MB, Asus A7N8X-E Deluxe, NVidia GF4Ti4200 video card - no crashes yet, XP
installed in May 2004.