I’ve run this on a number of PCs with great results and I would highly recommend doing it. Windows 7 is very, very good in having the right software even for older hardware. Microsoft did a great job getting the tech companies involved early on in the development process to make the right drivers and software to work with Windows 7. Those who adopted Vista early on (me included), had a ton of issues with hardware and software not working with the 32 and 64 bit version of Vista. Seems like Microsoft made the right decision this time around and I hope it continues for Windows 8 too.
You may download Windows 7 Upgrade Advisor here. You may get more information about the Upgrade Advisor here.