With a $2K budget, you've got a couple of options:

1) Use the majority of it buy two really decent mains and a sub
2) Buy the whole shebang.

Which option you pick depends on your priorities. Most of the nutjobs here (including your humble narrator) would spend that on the mains and take time building from there. Do it this way, and you'll end up a rig you can be happy with for a very, very long time.

Option 2 get's you into the theater right now. The challenge is that a good sub is going to run you 25% of your budget...at minimum...right off the bat. A HSU VTF3 Mk2 or Dayton 12" from partsexpress.com would fit the bill quite nicely for your room size, but now you have $1,500 left to play with. While that's not chump change by any means, it's not a lot to spread around for 5 more speakers. The ones that come immediately to mind would be rig based around four Epos ELS3's + CC, four Paradigm Studio 20's + CC, or perhaps four B&W 685's + HTM6. You'll need to negotiate with your dealer on the Studio's and B&W's, but if you're looking at JML 816's, I'm guessing you've already figured this out or you're willing to spend a lot more than you're letting on.

A couple of ideas for your consideration:
* Don't skimp on the sub. A boomy, crappy sub can ruin everything.
* Spend a lot more on the mains and cc as this is where 90% of the information comes from.
* Take time positioning your sub. How? Ask us or research this site under "Richard Greene".
* Buy a spl meter and test disc and calibrate your system.

Take your time auditioning speakers and enjoy the process. A great speaker can give you decades of enjoyment so remember, this is a marathon, not a sprint.

Hope this helps.