First use MacTheRipper to rip the copy protection off you DVD (only if it's commercial). If your DVD (I assume thats what your ripping it from) is a dual layer DVD (most current DVD's are) then you can use a program like Roxio Toast to compress (not clip it off) your VIDEO_TS folder and burn it. if it's just a single-layer DVD, Toast will just burn it without compression. Alos, Handbrake can convert you VIDEO_TS folder to a quicktime readable file for computer storage.
Ben