Thanks for the speedy reply and sorry for the delay, I was away from home yesterday.
This sounds like it might not be as easy as I'd hoped!
The purpose of the upgrade is to make my computer run as quickly as it's able to given the motherboard constraints, particularly because I want to play large, data heavy games like Football Manager 2013 and the game speed is too slow currently.
I hadn't planned to upgrade to Windows 7 but if you think it advisable then I would certainly consider it.
Looking at my system information, the current CPU is "x86 Family 15 Model 107 Stepping 2 AuthenticAMD ~2593 Mhz"
How does that compare speed wise to the others on the list? In your view, is upgrading the CPU worthwhile? And is it easy to update the BIOS?!
Many thanks again for your help.