Totally man, you sure can do that.
the Denon is a good reciever in the fact it makes it easy to bleed a 2channel system out of your existing HT even if you dont have all the equipment.
You use the amp with the pre-outs on the Denon (if the 2802 has pre-outs) and run the fronts off of the pre-amp.
the beauty is if you want to leave your existing HT setup AS IS and want to get a 2 channel system, you can do it somewhat like the way i plan to do it.
here is the way i plan to build out a 2 channel system out of my HT and eventually seperate them
Currently, i have the Denon 3803, with all 7.1 speakers.
Step 1, buy the speakers for the 2 channel setup. Use these as another zone off the surround back channels. Theyw ill be amplified off the reciever
Step 2) Buy a good amplifier. Then this will power the 2nd zone and the reciever can start powering the surround back channels and go back to its normal 7.1 setup.
Step 3) But a good CD player and some good cables. wish i had that pre-amp already
Step 4) Buy a pre-amp, then i can finally eliminate the Denon 3803 from the 2channel setup, and use the Pre Amp
At that point, i will have totally seperate systems, I will probably continue to keep them somewhat connected so i can use sources off the HT if desired.
The cool thing is before i even have the parts for a real good 2ch system, i will have a 2 channel system that ain't that bad.