Strongly urge you to look into the NAD line of receivers for home theater. The 700 series is excellent and within your price range; you won't be disappointed.
Some HT receivers that have gotten very good reviews lately: Yamaha 657 ($600 - Perfect Sound); Denon 2805 ($800 - What HiFi) though you can pick up the discontinued 3805 for about $1000; Onkyo 303 ($300 - Sensible Sound). Also, Outlaw Audio, which enjoys a reputation for manufacturing incredible performing; incredible bang for the buck components, just came out with a new $1000 HT receiver.
For a receiver, maybe also consider something like a used Pioneer Elite (43/45tx, 5_tx, etc) which should come in at way, way under your budget. As a college student w/ needs for "just" 5.1 I'd also guess you don't have a cavernous space to fill, etc. Looking for used deals on quality stuff like Pio Elite (or Rotel, Outlaw, etc.) can get very decent processing, adequate power, and money left over. Something like the 4X & 5X Elite series should be going for no more than $350-450 (or even better) and does 5.1 as well as anything. The latest & greatest is often just the latest - carefully selected used gear can get you huge bang for your buck. You might have to do a little research and have a little patience but the reward will be worth it.
Budget sub? Hsu would probably be #s 1, 2, and 3 on my list. I've used Hsu and it really did the job.
If you do go the used route (eBay or Audiogon, etc. and haven't done that before), I'd also suggest trying for something via local pickup. Either that, or check for quantity & quality of feedback and make sure you're comfortable parting w/ the dough.
Arcam is totally unique and supposedly excellent aounding. I like B&K and Rotel Recievers quite a bit. A friend, has the Integra (D-5 methinks) and it sounds pretty good too.
Paradigm PDR series subs have excellent sound for the money. The same friend with the Integra has a PDR-10, its rather impressive. Other subs to consider, of course Velodyne, NHT, and PSB, all offer low cost subs with a high performance to dollar ratio.
I have enjoyed a Denon 4800 that I bought used 3.5 years ago (my ex-wife has it now). You should be able to pick that up for a lot less than your budget and it is a pretty serious piece (the Stereophile review was also very good). The remote is not very good though, so you may want to spend the extra money on a third party remote.