Regarding running the vid signal throught the receiver or direct to the TV. Don't do it, go direct to the TV whenever you can. With a limited budget on the processor, what do you give up to get the upconversion? Sound quality? Quality of other components? Something! Plus why step on the signal.
On the TV side, that is an easy one. If you don't need the absolute, ultimate, highest end TV, go to Costco and buy a good Panasonic (Plasma is my recommendation). It comes with a lifetime customer satisfaction guarantee!!!!!! No extended warranty to buy, pricing is pretty competitive. If anything ever, ever, ever (did I stress ever) goes wrong with the TV, take it back along with the receipt (of photocopy) and get 100% of your money back.
I just bought a Philips 50" (factory refurb with 90 day warranty) at what I thought was a great price ($1,400 delivered). It died in 8 days and they reported it would take 6 weeks to be repaired by the local Philips authorized repair shop. I convinced them to take it back, which they did and even paid the return shipping. That day I went to Costs (1 hour drive) and bought the Panasonic and have no worries.
Do not buy a TV until you at least look to see what you closest Costco has available. They won't carry the ultimate in highest end TVs at $6,000 - $10,000, but if you are like me, a good HD TV is nice and really won't notice any real difference.
BOL on the house hunt