70% TV, well, who really cares about audio there.
20% movies, get a bluray player, and just rent them. Otherwise, with a DVD you only get roughly 30K pixels, whereas with BD you get a tad more than 2 million. That's not to mention the lossless codecs. Ok, I mentioned them, can your receiver handle them?
Well, with BDs, there are close to 200 titles with 7.1. I forgot how many 6.1 titles there are on DVD (always as DTS-ES, AFAIK).
Oh ok, I was about to say that I fear you might** be making more of a lateral move than a big upgrade, but I see that you only have a stereo pair of PSBs.
Send a PM to 3db as he's our representative PSB fanboi who also happens to reside in CA. He should be able to direct you.