Well you have many options for this:
a. If you have 2 dvd drives on your computer you can easily rip and burn a dvd in under 20 mins.
b. If you only have 1 dvd drive youd have to rip it to your computer 1st then swap in the blank dvd and burn.
c. You can rip all your dvds to your computer and convert them to a smaller file (ex. avi) then just stream movies as opposed to playing dvds all the time. This can easily be setup and done using an xbox 360 or ps3.
Im on a mac so im not sure about programs you can use to do this all if youre on a windows pc. But if you have a mac use instant handbrake to convert dvds to other formats, or use Toast to rip and burn.
Hope this helps....