What's the best CPU I can upgrade to? Can I put a Core i7 920 in this mobo?
Is there some socket terminology I should know as I look into this? (E.g., what socket do I have?)
No you can't upgrade to an i7, your mobo is a socket lga 775 while the i7 is in the 1366 socket,the i5 and the i7 860 are in another socket as well, the 1156 socket but let me brak it down
socket lga 775- Core 2 duos and core 2 quads (for the newest core 2 chips that came out last year or so make sure you check the model of tof your mobo on the internet and see if they are compatible some older lga 775 mobos can't handle the latest core 2 quds or duos)
socket 1156- intel's latest mainstream line to replace the 775.....this socket carries the core i5,core i7 860 and the upcoming core i3
socket 1366- intel's latest high end line carries the core i7 920 and above (all with the prefix core i7 9xx) comes with triple channel memory and some other extra perks that you won't find int he 1156 line up.
In you case the best you could possibly upgrade for is the core 2 quad 9 series or so but you have to see if your mobo can carry that chip first,just find out the make of your mobo and the model number on the website of the manufacturer and you will know.
If you only want to upgrade the CPU then you need to find out which motherboard you have in your PC as this could affect your choice of CPU's
google / download CPUz and this will give you the necessary info on the motherboard maker and model number. Head over to their website and look up which CPU's it supports and go from there.
The E6600 is a socket 775 chip and has been recently replaces by i5/i7's and as such you wont find any new releases. You will find some decent quad core socket 775's out there and prices have dropped recently due to the newer socket / chips