I actually had a lot of problems with sound quality in an array of programs. I went through 3 uselsss microphones until the 4th actually got me nice quality. I can't tell you why.
Susan53 - Audacity works pretty much like a tape recorder. Just hit record and then start speaking. You can do some editting an mixing in the program, but you might want to tinker with that later.
Sound Recorder will work just fine as well.
There are some programs that will record Skype conversations as well. I believe there is a free one, but the one we use at
www.eslteachertalk.com is AudioHijack