There is a fairly useful writeup about new TVs, UHD vs HD in this month's Consumer Reports.
Refresh rate is most simply explained as a fix to help overcome picture "breaking up" occasionally during stuff like lots of very high speed sports action filling the screen.

It is sort of ironic that as mass produced residential TVs get more and more technically advanced, and 1000 channels from cable companies are not much of a stretch, at least 95% of all programming on a good day is cartoonish garbage.

Samsung and LG are generally considered good value for the asking price. But be sure to buy the reasonably priced extended warranty that can be had with it at Costco or where ever.

"Refresh rate" - I see listings with 240 Hz and 120 Hz - indicates the speed that the screen redraws the picture lines. It is important in fast moving action scenes like sports action. Most HDTV of a medium price point already have this in it!

"Resolution" I see 2160p (4K) and 1080p - is the quality of the image basically. If you are using Blu ray players then you get full 1080p but if you are on cable/dish; then you looking at 720p or sometime lower resolution. Old TV programs were broadcast in 480i which is lower then 480p. Standard DVDs are in 480p or lower resolution depending on what the material is - movie is best; TV programs depending on age: 1950s where lower resolution recordings then 1960s,1970,1980s age. 1970 and beyond are good 480p recordings until HD took over. Mostly all HDTVs provide a double scan image technology where it boost the image density to close to 1080i for your standard DVD images. So if it the image on the DVD is poor; it looks even worse and if the image is good; it looks better.

Not much is available for 2160p yet but they are working on it! Most current movies are filmed over 2160p. The trouble is that there is no DVD player that can play that high resolution other then hard digital storage media - computer hard drives, flash drives, etc...

If it were you; I buy a bigger TV then 55". But that personal choice! I just get an average HDTV - 1080p; since they are commodities right now! Dirty cheap! Some TVs have built-in Wi-Fi with built-in apps for Netflix, Hulu, etc... I just went with Roku box since technology changes each year and the new 802.11ac is going be the standard. 3X faster then 802.11n.

I have a 70" HDTV myself! LOL!

2016p is a long ways away in having any media to view and cost a fortune too!

Unless you watch a lot of sports going with the faster refresh rate (240hz and up) isn't going to needed. Besides a lot of this refresh rate improvement are done with smoke and mirrors electronically speaking.
UHD (4x) is in its infancy, you may notice it in a larger TV above 55" but the value just isn't there nor the content. Even now you don't get 1080p (1080 dots vertically and 1920 dots horizontally) content from most providers. Its either 720p or 1080i where "i" means interlaced, which is it draws every other line and then goes back to line 2 and then does those 540 lines. You get true 1080p where p is progressive watching BlueRays and some providers. But there again some of these providers are giving you 1080p by upscalers taking lower resolution content and "guessing" what color the missing dots should be (using some pretty fancy math).

Bottom line, if you having bought a HDTV before, you will be astounded with a 46" -55" 1080p / 120hz picture at normal watching distances. No need for 4x or 240hz or above. If you go with a 32", you won't need 1080p, 720p is fine. If you do the math you will figure out the dot density is about the same on a 32" 720 as a 55" 1080, which it's really all about.

Also, 3d is not worth it either, just a gimmick to sell more tv's. Who's going to wear those stupid glasses anyway. They give me a headache.

Yes, get the extended warranty at Costco with a Samsung, LG or Visio. And get a smart one that you can get Skype, netfix, youtube, etc. with a wifi connections. I would say $800 +/- $200 would be the price.

Here is a good site for finding info about things:

http://en.wikipedia.org/wiki/Main_Page