-What is the difference between Vista 64 and Premium and Home…??
-Is there a lesser of these three "evils"?

the answer is by Self B :
1) memory consuming
2) complex OS
3) many features are disabled to be unlocked only after purchase license
4) Xp is simpler
5) many vista features only add to beauty than fucntinallay (comparituvley)
6) specila h/ upgarade required
(example 2gb raam etc)

Yet if u have a good hardware and purshase it legally . its perfect experience

All the best
Hope this helps