You will get all kinds of replies to your question. First, I would look around you local area to see who could help you get the most bang for your buck. Try videoguys.com for a basic outline for your PC. Get all you can get, cause, if your school system is like most, you will not get any "new" equipment for a while.
Adobe Premier, Pinnacle Liquid, Avid Xpress Pro and Sony Vegas 4 + DVD are the current "big dogs". I just bought Vegas and have found it to be a delight. Vegas will also run well on a humble computer. The others I listed run best on the latest high horsepower computers.
Don't waste your time with any of the low end editing programs, most of them are good for limited home use. However, for your 2-3k budget, get can get a lot of pc and program.
Hope this helps.
Changed like Saul,
Chris Folsom
Folsom Audio & Video Productions
http://www.pbsermons.org