Yea what he said is pretty much I was saying to do. I personally would just record in full quality (if you have the space) 1 video at a time then encode the higher quality video to something smaller to lose less quality.
I see your attempt at it it looks swell but I laugh and hand you this:
Blu-ray Ripper - Rip Blu-ray to video converter, create DVD and transfer iPhone files
For 30fps for about 1-3 minutes yes sir, you'll have the same size like I do when I record.
Record at 1 hour and sweet jesus end up with a 35gb+ file.. #_#
Been using the blu-ray ripper since christmas 2010, file sizes it produces is wonderfull even when played on a cheap phone it looks sexy most times.
Also I want to teach you a trick I learned with fraps, if I can get my wireless adapter working I'll contact you late tonight.