DVD Compression


i've started to make back up copies of my dvd's on my g4 12 inch powerbook. the problem is i've run out of space on my computer, and i can't an external hard drive because i'm a lil short on dough. So is there any freeware/shareware programs out there tha twill allow me to compress my dvd into smaller files. something like dvdfab for windows is what i'm looking for.