The CPU is fine for a 64 bit OS:
The rest of your PC is probably Ok, but you should check Microsoft's website to see their requirements.
Thanks for the reply. I did download the Microsoft Windows Advisory and ran it, which says I need to install 32 bit. My processor is E6500R and not E6500K; do you think this makes a difference, as I see you've referenced the K?
Well, Intel does not list an E6500R on their web site, but E6500 is listed, check the link below:
The E6500 is a 64bit CPU, and the differences between the E6500K are minimal and insignificant regarding the OS. The MS Windows Advisory may be recommending the 32bit OS due some 32bit software and/or drivers installed on your PC now. Your mother boards G41 chipset will support CPUs up to the Core 2 Quad 9000 series, so the board itself is not the limitation. Do you have 1 GB or less of memory, that might limit you to a 32 bit OS.
Besides having 32bit drivers and software, or a small amount of memory, I don't understand why the Advisory program recommended a 32bit OS.