I have already done this the previous replys about divx are the way fowards if H Drive space is at a premium, but in my case I did not want to loose to much quality and plus i have over 20 Tbs of hard disc to use so ive used various bits of software including CloneDVD & DVDshrink either will allow you to rip to a folder on your hard drive. Yes they will be large files anything between 3 to 4.7 gig files dependent on what type of film it is also I only backup the main film files without any extras (They are a waist of time)
Obviously DVD's have protection built in for good reason but as long as these are ripped with your own use in mind thats fine.
If your using MCE windows you can make it see and disply your ripped DVDs
HERES THE LINK WITH INSTRUCTIONS
DVD SHRINK HERE
Clone DVD you will have to pay for im affraid also you will need AnyDVD that works alongside it etc
Hope it helps PM me if you have any specific questions!