It is not a problem. Go here:
Link Removed
and download the version you want. It is perfectly legal. Be sure to obtain a key at the same time.
If your computer is 64 bit capable, you should have no problems. Hardware compatibility should not be a problem either. You might have to search for some drivers if you have "one.off" hardware.
Whilst you are on the Microsoft page, download the 32 bit also, then you have the best of both worlds!