whichever you have a license
for is the best. I'm running XP on the netbook I take on board and am happy, but almost all the testing and development do on 7 and am happy, no difference in stability. Don't know how the drivers work
in Parallels, but if you don't have any problematic hardware
, you should be fine with both. Battery-wise I don't think there's a chance for much difference in the emulated environment
. Having a Mac I would probably at least test the Mac builds from Pat...