The full version of FRAPs 2 will record for as long as you have harddrive space left (About 1 minute of video can be in the hundreds of MB's)
The only (legaly..) free way aside from FRAPs (I've searched for free FRAP-alikes, but no luck..), is if you have a TV/S-Video out function on your graphics card (Most modern cards have this, I've even seen really old 16MB PCI cards with a TV-out, though..), and (If possible) a second PC with a TV (In) card..
You could possible do it on one PC, but it may or may not work..
But basicly you connect the S-video out port to the TV card, and record the Composite-In (S-Video) with a program like VirutalDub
If you record it with a second PC, there is no performance hit on the game machine at all, which is very good..
It's a good solution, but if you don't have an uptodate graphics card, and a TV card, it won't work :-\
- Ben