Bardcat,
Thanks for your post and welcome to the forum.
If you are going to stay with SD signals, you might want to consider what those pictures will look like. Most retailers have the ability to change the channels in the store to display SD; this way, you know what to expect. As a guy who has looked at televisions (for fun as a kid, and critically as a professional) for many years, I will readily admit that I am not a fan of watching SD programming on an HD television panel. There is only so much that processing CAN do, and while Auto Motion Plus does have the ability to improve the picture, the result may not be what you expect.
If you want to make the best decision based on facts, I definitely recommend you check that out so you know what to expect.
For applications such as Blu-Ray or Video Games - this is where AutoMotion Plus is going to give you the real picture difference, as it will with HD content. Depending on where you live, you may receive some of your favorite programming in HD using an OTA antenna.
As far as "the amount of space between screen and face", I recommend using the 3x Rule of Thumb, and then adjusting to your preference. If you're going to have a 40" panel, you probably want to be sitting at least around 3x that - 120 inches = 10 feet. This allows your peripheral vision to encompass the entire screen without having to constantly move your eyes, which can cause eye fatigue and take away from the overall television experience. That said, I've spoken with people who sit 5 feet away from a 63" panel and love it.
Most people choose a panel between 2-3 times back (Rule of 3x is just a starting point), so typically, that panel may work for 6 feet - five feet being where the couch begins, and then that extra foot for where you're sitting back ON the couch.
Stand back from the panel in the store about where you think you'll be sitting and relax your eyes while looking at the picture. Can you encompass the whole picture? Will that be relaxing, or will your eyes have to constantly be alert?
Usually figuring out where you like to sit in the movie theater will help you decide.
If you're a back-of-the-theater kind of person, Rule of 3x applies applies to you with little adjustment.
If you're a middle row kind of person, you have some leeway.
If you're a front-row viewer, we have a great 52"
I hope that answers more questions than it creates, but I believe in being upfront with a completely no-pressure attitude and discussing the technology to your satisfaction.
Let me know if you have any other questions.
--HDTech
Hi there, I?m looking to buy my first TV after having years of hand me downs. I am torn between the Samsung LN37A550 and LN40A630. Both look great and I?ve seen both on display. I like the idea of 120hz in the 630, but I am on standard digital cable with no plans of going to HiDef. Will 120hz make the standard cable appear less pixilated or will it matter? In other words, will it look better than it is on my Zenith 26? CRT TV? I don?t like the ?soap opera? look to movies at 120hz, but will it make a difference watching sports? What about general sitcom viewing on standard def? If there is no real benefit to 120hz I will go for the LN37A550 as my living room is average size, but the 2 couches are 5 feet away from the screen. Will a 40 inch overwhelm my viewing enough to drop down to the 37 inch in order to make it bearable? I fear if I get the 40 I will be getting headaches and bug-eyed. Either one is a coin flip right now, but I want to make a decision based on the best facts. Thank you.

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