A lot of the problems people have with FRAPS is due to how they've got it setup.
TBH it doesn't matter how slow your pc is, you'll be able to get full size 60fps video with no lags easily.
On the 'video' tab in FRAPS do the following:
Set the video size to full-size
Set the FPS to 60
Turn on the hide cursor option
Turn off record sound (unless you need it for whatever reason)
Turn on the no sync option
Even though the game will lag like hell, you'll get a perfect video out of it. It's the no sync option that makes the difference, as it removes any lag that you see when recording.