I use Fraps for all of my video recording. It does use a decent amount of resources; however the depth and quality you get from the clips allows you to do a lot with it. Depending just how much editing you want to do.

Windows Movie maker is a great program to start learning the basics, I started that way. You can make a video with it, the quality isn’t great but you could get by with it. For the more advanced editing software there are only three choices. Adobe Premier, Sony Vegas, Final cut pro (Mac).
I started with Adobe, and then later tried Vegas. I liked the feel of Vegas and could navigate the software much faster and its layout was easier for me to work with and understand. You can try both (free trail downloads) see which one you like. Last time I looked Adobe was $400+ and up. Sony Vegas was $120 I believe (from memory a long time ago).

Adobe you may find more resources on the net as it’s more popular and has more things available for it, and some guides already for some “How to’s” with wow video. You can find the same with Sony, just not as much.

I would like to switch to adobe soon (it’s not something you can just pick up and go). I’ve reached a limit on the things I can do with Vegas and I just can’t find the resources I need to do some of the things I want. Keep in mind however I’ve been playing around with the software since 2003, so it’s taken me this long to get to that point.