16 Western Digital 1TB drives in RAID6. I wrote a web frontend to manage and launch all the content that ties into the array. Works great. People worry about corruption and drive failure, but I've been running this since 2007 and only ever had 2 drives go. When one of the drives failed, being RAID6 I had still another drive as a safety net until I was able to get home and replace the failed one. Three drives have to fail before you lose data. Pretty safe IMO, so long as you don't do something boneheaded like store the server in a hot closet lol.
For DVD storage, I like
this storage rack.
PS, in addition to the array as online storage I also have offline storage. The drive in the 5.25 bay there is a Quantum LTO2 Ultrium tape drive. Tapes have a shelf life of 30+ years if stored properly, so it's a very stable medium to use for backups. I need to upgrade though to LTO4, as my LTO2s only hold around 180 GB. I'll probably do that when I build the second server (my 14TB volume currently has 340 GB free lol)