Re: refresh rates (60 vs 120) - the answer is "depends on who you ask" (and what you're watching. Generally, film is shot at 24hz (DVDs), so you have to do some conversion on a 60Hz TV (not divisible by 24) while you do not on a 120Hz Tv (divisible). This affects the picture to some extent (the 120Hz covers more refresh rates, and the 240Hz even more) - see http://en.wikipedia.org/wiki/Moving_image_formats. However, many people find the 120 and 240 TVs to be so sharp that they seem artificial, so it kind of depends on your own opinion. I would try viewing some side by side and decide what you like.
And, yes, contrast ratios matter (higher is better), but there are also differences in measurements across manufacturers, effects in different lighting, etc, so while it is a rough guide, again you have to see what you like. YMMV.
Pretty much most, if not all, TVs will have a tuner these days.
Had not heard that about the 60 HZ vs 120 HZ in relation to the FPS. My understanding was that the issue would be ghosting on fast action scenes.
The 24 vs 30 frames comes in when you're watching a progressive scan DVD and the TV set you have does the 3:2 reverse pulldown. So if the set doesn't have that or you are watching TV, then everything you watch will be at 30 FPS making the 60/120 argument irrelevant?
http://www.projectorpeople.com/resources/pulldown.asp
I second that you should view some of the sets first to get an idea what suits you.