Pirelli Nero M&S... get 225's. they're all season and have great wear characteristics. but they also perform well. i had a set on my old '02 WRX, and have a set on my STi now. they're very predictable and it's easy to tell when they'll slip and when they'll get traction back. i've had my STi cross country twice, up and down the east coast numerous times, in auto-x, and in drag racing. for an all-season M&S tire, they're great. and they will be a HUGE upgrade compared to the craptastic stock WRX tires (if that's what you have now). those are the worst tires i've ever driven on. the Pirelli's are $125ish/each for 225/45R17's, so they shouldn't break the bank.

i'd suggest getting wider wheels while you're at it if you can, though. 17x7.5 or 17x8's. check out Rota wheels, they're very good quality for the cost.