If you have access to a Mac, use Handbrake (I think they also have a Windows GUI) with the "High Profile" preset at RF=18, and two audio tracks - the default High Profile audio (stereo mixdown) and then an additional AC3 Passthrough (for 5.1/etc.) on the second track. The mixdown to stereo allows for audio in the iPad. Or, just rip all your DVDs in RF=18 and AC3 passthrough, and then re-rip the saved file and downmix the audio with Handbrake for when you want to transfer it to the iPad, which is how I do it since I don't need a stereo track for each ripped movie. The iPod/iPhone will require a separate rip at a reduced resolution, so you can convert that from a saved rip only when you want to view/transfer the file to the iPod/iPhone.
My recommendation (and what I do), which is mainly HT setup:
-Get a Mac Mini, low end is fine. HDMI and Toslink cables from Monoprice. Bluetooth mouse and keyboard.
-Use Handbrake with High Profile and RF=18 with AC3 passthrough: it will give you 1.4-2GB movie sizes that look amazing, as well as surround audio. If you keep the default stereo downmix (to be compatible on the iPad), add another 200-300MB.
-Get a OWC FW400/FW800 SATA dual SATA drive enclosure from Other World Computing and two 1.5TB Samsung F2 HD154UI drives from NewEgg. You'll have a dedicated 1.5TB for media, and one drive for backup.
-Download Plex (plexapp.com) for a HT software. Setup the movie/TV scrape server options to download data.
-Launch Plex from the keyboard while on your couch. I also use OneKey, $5 shareware to assign a unused F-key to Plex (I use F5).
-Enjoy your movies.
Questions? Ask away.