I made this a little confusing with my response. What I meant was that you did not need to use iTunes on the computer to download the movies - and of course, I left out the part about "on the computer". You still have to download them using iTunes on the iPad. My apologies.
I have never ripped a DVD to transfer into iTunes and then sync it to the iPad, so I couldn't really help you with that. If you search the forum using the Search Communities in the upper portion of the page, you will find lots of discussions about how to do that. Using a Google search would turn up lots of hits as well.
I think that the 40GB of storage was overkill, but like I said, it depends on how many devices you are backing up to iCloud. If you had 4 or 5 iDevices that are 32GB or more in storage capacity, 40GB might work for you. You can use one iCloud account with multiple devices and if you take lots and lots of photos with all of your devices, you could conceivably need or want that much storage for backups.
Camera roll photos are stored in the backup and photos take up a fair amount of storage space. But if you had tons and tons of photos, I would recommend importing them to your computer and storing them on an external hard drive as well. Even though all of the photos would be in the backup, you cannot retrieve specific items or files from the iCloud backup. If you restore from a backup, you restore everything in that backup to the device. Whereas if you are just trying to locate a handful of photos to restore to the iPad, you could do that by retrieving them from a hard drive and sync them back to the iPad, email them or use a WiFi transfer app for that purpose.
If the only device that you are using for backups has a 16GB storage capacity, it is impossible for you to need more than 16GB of storage in iCloud. You can't possibly exceed 16GB of storage on the iPad so you couldn't possible have 16 GB of data or photos to backup.
I hope that answered your question.....And I hope the Steelers have a better year than last year. So many question marks this year...but I never give up on the Black and Gold! Go Steelers!