I really don't think a good free screen capture program exists. Trust me, I've looked quite a bit for one myself. I'm no professional, but I'm pretty certain your choices are down to Fraps and Dxtory. There are 2 basic differences between them.
- Fraps is more user friendly while being less flexible than Dxtory
- Dxtory is more reliant on hard-drive writing speeds (why I can't use it for now) but with slightly better quality
Also, if you'll be recording Minecraft, I would suggest using a tool called
Sizer which allows you to have fine control over window sizes. To record at 720p, I set my window at 1298x765 because Sizer counts the borders. It's likely to be slightly different for you, so I would test it just by starting around there and taking screenshots in game and looking at their resolutions.
If you need to upload or edit the video I've got more tools you can use. I hope this helped.