I absolutely love Pro Tools, but then again I've been trained in it. There are definitely some very cool noise reduction plug-ins, but unless you understand theory on audio and what knobs control what part of the sound envelope, then it can be a very daunting thing.

You could try Audacity, like Crono said. I've never used it, but if it has a simplified noise reduction plug-in then you might be able to get away with it. But again, I have no idea what the tools are like in that program; my guess is they are simplier because it is open source and free.