I'm no expert either, but I'll weigh in... I'm thinking clips of at least 2 songs, but 3 is probably already a stretch in 30 seconds. Obviously, these should be clips that are most likely to blow people away at the first listen, I'm sure you've gotten enough feedback by now to what to pick from... also, if you have an interesting instrumental passage (and I know you do... )... you might be able to talk over that. The more music the better. Your music speaks for itself, and your audience won't be much influenced by hype anyway, so you say the minimum, some back ground and where to buy. Be sure to mention your name and the album title 3 times. Seriously.
Having a distributor doesn't always guarantee you're in stores, YMMV... plus, I'm not sure how much distributors care about getting a plug... but retailers sure do, especially in this shitty economy... so if there are any major stores that you know you're in you might offer to mention them by name and see if they don't comp you with a counter-card or some premium rack space.