I'm running Windows 7 on 2 laptops and my desktop at home (via clean install), with 2 other laptops running Vista, and I can see a difference, it's faster to install from scratch, loads up the drivers automatically, and is generally quicker than Vista even running on a 32-bit system.

I know my desktop can handle the 64-bit OS, but haven't bothered with it yet. You don't need another processor in your desktop, it all depends on your current processor.

For example, my desktop CPU is an Intel dual core E5300, and from Intel's website (http://processorfinder.intel.com/det...px?sSpec=SLB9U) I see under Supported Features in the 3rd bullet point, it says Intel (R) EM64T, which apparently means it supports a 64-bit OS.

Hope that helps.