Update...
First off, thanks to all who posted. It was a great help.
Bonus time rolled around and it's been a good year. After much research and comparison, the follwing items were added / replaced in my audio system.
Yamaha RX-V2600 Receiver (replaced HK AVR 520)
Yamaha DVD-C950 DVD Player (replaced Pioneer)
SVS PB-10 Sub (replaced Sony)
Sony Grand WEGA 42" HDTV (replaced 36" Hitachi)
I am thrilled with all the equipment. It works well with the JBL speakers. The PB 10 simply kicks ***. My whole room shakes.
Now on to the hookup headaches. The most confusing issue is the upscaling to HDMI that the 2600 is capable of.
My DVD player, DTV receiver, Yammy Receiver, and TV have HDMI ports. As i understand, using solely HDMI connections will only pass through. This will leave older analog TV and DVD signals at their native resolutions. If this is true, would it not make more sense to use component video connections from both the DTV receiver and DVD player to the Yammy, then to run HDMI out to the TV. This should allow upscaling to HDTV resolutions for everything. Can anyone with a similar configuration confirm or deny this logic?
Lastly, my old components are available if anyone is interested. The HK receiver center channel sounds like a tin can, but everything else (ie pre-amps) is fine. Lemme know otherwise they are going the eBay route.