Well, you can install pretty much any version of Linux on that PC and it will run fine. You don't say, but I'll assume that's a 64 bit processor, so you should install the "X86-64" version. (Most 64 bit PCs ship with 32 bit Windows, which makes about as much sense as selling a V-8 engine with half the spark plugs pulled out.)
There are countless Linux distributions, but for the new user "Linux Mint" is probably the best choice.
More information at the link below.
I've been running a 1.68 GHz Core 2 Duo with 2 GB of memory for many years now, and it is plenty fast for everything but the FlightGear flight simulator that's available for Linux. Currently running Fedora 18.