Can someone recommend a good speaker system for a blu-ray player?

You'll need a surround sound receiver to drive those speakers. A good inexpensive brand is Yamaha (their basic stuff - their top-of-the-line stuff is pretty pricey, but probably overkill). You're looking at about $250 new in the box.

I always recommend Klipsch speakers. You can get a new set of Klipsch Quintets (5.1 set-up) and a Klipsch SW-12 powered subwoofer on ebay, delivered, for about $700 (or $600 for an SW-10 instead).

Even though you're watching blu-ray movies, I think anything more than 5.1 surround sound is overkill. You're paying more for the receiver and more speakers, you have to run the wires everywhere, you have to have a place for all the spekers, etc. It's just not worth it, in my opinion, unless you're specifically building a home theater room.

You don't need a speaker system, you need a receiver with an HDMI input. And if you want the full HD audio experience, you need a 7.1 receiver. I recommend the Onkyo 606, you can get it for under $400 shipped from amazon. But you need some decent speakers as well. A good receiver will sound like crap on crummy speakers.