I'd suggest obviously running the upgrade assistant to see if your PC's processor has the supported features to run Windows 8, such as PAE.
Considering you specs, I'd run Windows 8 over 7. You save on system resource hogging, at least about a good 100 MBs over 7. Performance is straight up faster than 7 on older hardware, and it will probably feel like new life was breathed into your old PC! This is true.
Since your PC has driver support up to Windows 7 right now, very good chances are that you'll be fine in that department. My concern however is the graphics driver support, you might not be able to run the native screen resolution of your monitor. I'd go for it, but I'd also make a hard drive partition and installing clean within that newly made partition to see how everything runs before you switch over.