i use a 2.0 setup for my comp too. I have the behringer b2031p which I love. I dont have a receiver, but i have a 2 channel amp that works well. The smaller b2030p are also great for their cost.
Personally, I would stay away from active monitors. Although it might seem like it would be easier to have everything in one package, you lose the ability to use the speakers in a different setting (like in a surround sound setup as you mentioned).
I had the klipsch promedia 2.1 before I had the behringers, and they have their trade-offs. The klipsch had better low end because of the sub, but the mids and highs are a lot higher on the behringers. If the lower low end bothers you, you could always add a cheap sub.
P.S. always check craigslist for awesome deals on amps and what not. They may be hard to come by, but its definitely worth it.