use this for software and hardware also at the bottom of the page there compatibility test that will tel you if you could run the 64 os and what missing to run it http://www.microsoft.com/windows/compatibility/windows-7/en-ca/Default.aspx
Okay, so I ran the compatibility test, and posted the screenshot below. I also found the exact model of the PC from gateway's support website, hopefully it will come in handy.
Link to Specs : http://support.gateway.com/s/PC/R/1008835/1008835sp3.shtml
I also went ahead and installed two different ram modules. I removed the 512mb of ram (2x256mb) of Corsair Platinum Series CMX256A - 3200C2PT (picture below)
and replaced it with 1gb (2x512mb) of Corsair Value Select vs512mb400 (picture below)
So now my new question is, can I install all 4 sticks of ram onto the motherboard even though they run at different voltages?
Thank you again for the help.