I highly recommend hypercam because it has a lot of compression settings that you can change to get the highest quality video. Camtasia is the best packaged though with its ease of use and good quality video.
I use a "special" version of fraps and I'm quite fond of it, I'd recommend it. I don't experience any additional lag from fraps and the quality is great.
This is all my opinion so take it with a grain of salt. I'm not trying to sell the product just giving my experience.
The free version sucks ass and only captures for 30 seconds or something lame like that. If you can get your hands on a "special" version I'd recommend it.