Without a doubt, FairUse. It used to be free, but it's worth the small fee. It has tons of options to play with to get it to whatever quality/file size you want. I've found that around 10MB per minute is a good trade-off. It results in an average of about 1GB per movie, but that's not too bad. And I think that's a good plan of yours. You'll probably save a bit of battery power playing these off the hard disk than constant spinning of the DVDROM.