What should I look for in a Processor??

What type of coding is neccesary?? Do i need every dolby, thx, etc. which settings or features are most important. I am thinking about purchasing a used one and it appears some have component video switching, not sure how many are HDTV cable through this switching due to their age. I could very easily just run the video directly to the tv if this is a problem.

thanks for the help..
Not being a super video buff, I am strongly of the opinion that one is better running the video signal, either from the cable converter or DVD player directly to the TV (assumably via an HDMI output/input) and just taking the audio signal to the pre/pro.

Additionally, I am in agreement for the most part that buying used processors is the way to go. A unit that is only 1-2 years old can be purchased for a fraction of the new price (ie. about 25%) and I have found that the processing offered in these sub 5 year old processors is perfectly fine. But again, I am not a true HT/video buff but much more concerned with 2-channel performance.

For the record, I have heard both inexpensive used (ie. a couple year old processors) and brand new expensive processors (in my system, McIntosh MX 132 at the time and a new Krell HTS 7.1 2007 model) and for HT don't feel that there is a noteworthy improvement in buying the latest and greatest. This may not be the case in the $10,000 range processors, but has been my experience. I found that I received 95% of the pleasure from my old Acurus ACT w/ ABM as I did with either the McIntosh or Krell for HT (not necessarily 2-channel) and these can be purchased for under $350 used!
The most important item for me was DPL II. Way better than just pro logic for normal tv. The next issue I looked at was the DAC. I wanted nice clean sound (24/96 minimum). Third issue was the remote-easy to use/program. Last item was enough inputs and outputs for your needs.

Also, check out size. Some units tend to be wayyyy to deep for most cabinets.
Most of the TV's these days have more than one components, DVI's and/or HDMI inputs for you to run your source(s) directly into it. This should take care of most if not all your video needs. That said, i would recommend buying a used B&K Ref 20, 30, 50 or Acurus ACTII to perform the audio tasks and you're all set without spending a lot of money. My system consist of top of the line CJ gears (CJ gears are mainly for 2 channel listening) with five awsome speakers from Usher, BE10's, for fronts, center, and surrounds and i still use the B&K reference 30 that i bought 5 or 6 years ago without any issues. I ran my blu-ray and dish directly into the projector via HDMI and component, respectively. My advice is NOT to spend a lot of money on surround sound processor unless the latest/greatest is a must have for you..... The direct answer to your question is to buy a used B&K pre/proc starting with the reference 10
Ginas makes a good point, especially if you care about 2-channel performance. Get a pre/pro at a budget price such as he has mentioned, and later spring for a decent 2-channel preamp with HT passthrough for 2-channel listening as most of the pre/pros don't do that well in 2-channel. I had the B&K 507 S2 and also the Acurus Act III with ABM. The Acurus is somewhat prone to ground loop hum issues so be prepared if you go that route. Once you take care of the hum once, it is taken care of, but still takes a good day to properly correct it.