We have an LG and have been extremely happy with it. As for refurbished, tosy's TVs are completely different that before digital. If a TV has a problem right after it is initially purchased, and the factory takes it back, fixes it, then sells it again with the same warranty as when new, it is usually a good deal and will not five you any problems. But if someone else tries to fix it, it is likely not a complete fix and check-out, so I would avoid those.
Only go refurbished if it comes with a good/decent warranty. No such thing as best brand, but their are good brands, such as Sony, LG, Samsung, sharp. Insignia and vizio are decent if your on a budget. Remember you can't go solly based on brand, as top quality brands can have a bad model. Always read reviews and compare features to get the best bang for the buck.
Everyone will probably say Samsung. I have two of em and don't the picture quality, it's clear but over saturated. I personally like Vizio's video quality better thought there are plenty of great brands like LG, Sony, and Sharp, up to you to choose which you like best.
Samsung I think makes the best TVs. I've seen them all close together in stores other than Best Buy. They are usually the most expensive ones though. I currently have a 6 year old Toshiba that is still going strong because it was the best priced and highest quality picture I saw at the time.