Two things, will the system be used for a combination of movies and music? TV watching as well? Speaker selection might vary depending on how much music use you'll be doing, depending on your tastes. I'd demo several different brands, and include the Kef Q series in that list. And for movies, a center channel really adds to the experience.
The other thing is, does your budget include buying a display, or do you already have one? I would suggest that your display and your speakers should take the lion's share of the budget. I concur on the Denon avr, though depending on money left, for a sub you could save some and get a HSU Research VTF-15H for about 1000 shipped.