I find that my recent DVD purchases have been TV series. Like what was said by Mr. Hankey, getting more than two hours just gives you more time with the characters, and I just tend to enjoy the stories more when it feels like I "know" the characters.
Sometimes it even gets TOO addicting. Some shows on DVD I have watched in ONE sitting: Lost Season 1; 24 Seasons 1, 2, 3, and 4; Firefly; Chappelle's Show Seasons 1 & 2; Entourage Seasons 1 & 2. After watching the last episode of the season, (sometimes sitting in front of the screen for almost 20 hours!) I'm still thinking, "I WANT MORE!!!"