I think it's kind of a personal thing. It may depend on how good and/or sensitive your eyes are, what your lighting is like, etc.
All standard LCD monitors for the PC are designed to run at 60hz. They usually look their best if you use a DVI connection instead of the 15 pin D-sub.
LCD's tend to look best in their native resolution, so if you get a 17" with 1280x1024, I would recommend running it at that resolution if you are able to read it. They make 19" LCD's that do 1280x1024 so the same info is stretched out into a bigger area to make it more readable, which some folks prefer. The downside of that is the pixel density is not as good, so the display can look a bit "blockier" depending.
For anything besides gaming, I find that the 20.1" form factor with a 1600x1200 resoluton works great. I say besides gaming because for one reason, you have to have a really powerful system and video card to get all the games to run at that native 1600x1200.
Anyway, I have a Samsung 204b, which gives you great specs for around $300 after rebate. Amazingly good deal, and it has both Contrast and Brightness settings to help you customize the display to meet your preferences.
To me, pixel density is a KEY factor. Cleartype is almost a must for most folks when using an LCD with XP, and it tends to look better when you have a higher pixel density (more dots per inch = clearer, more refined pic). So 1600x1200 - a true 4:3 aspect ratio - on a 20.1" LCD looks fantastic to me.
For gaming, I much prefer a CRT, so I have both on each of those 2 machines.
I would recommend going to the store and trying a 17" with 1280x1024 and a 19" with 1280x1024 and then a 20.1" with 1600x1200 and see what works best for you.
If you dig a CRT, then hang on to what works or snag a nice Viewsonic G series.
I think overall, the key thing is to get the monitor that YOU feel more comfortable with. After all, everybody is different and these are YOUR eyes we are talking about here.
I have both and prefer CRT, especially for gaming. I HATE gaming on an LCD unless it is in its native resolution, cause it just looks BLECH to me. Those 17" and 19" LCD's are not a 4:3 ratio, so if you run your game in 800x600 or 1024x768, they will be distorted if you go edge to edge.
With an LCD, I find I have to have VSYNC on if I play a game. Therefore, I need to have TRIPLE BUFFERING on to avoid stuttering. Not all games support that, so that too can be a pain if the system can't keep up with 60 frames per second.
Plus, with an LCD, you have to decide if you want to scale the image edge to edge in non-native resolutions, or you want to have the image locked in the middle of the screen at its actual pixel size (with black bars on the sides and usually the top too).
With CRT's, all of that stuff looks way smoother because the way the tube works. Non-native resolutions usually look just as smooth as the max res, depending on how you have it set up.
If you are into color matching, CRT's still have the edge there too, but that's more of a pantone technical issue that may not be relevant to your situation.