What Specs Needed 4 Lcd Tv (37″- 42″ Range) 2 Get Clear Crisp Colorful Pic Even When Watching Action Movies?

Go with a 42″ Plasma then.
LCDs are inherently flawed with fast motion playback. They suffer from motion blur. Manufacturers compensate for this with 120Hz or 240Hz refresh rate options. While they help the issue a lot, they are not 100%. And you have to pay a heavy price premium for them.
Plasma is inherently near instantaneous in its response time (like CRT/tube and DLP sets). So it will give you a clear, crisp, image when watching action movies. If you see Plasmas advertised with like 480Hz or 600Hz sub-field motion drives, that’s not a refresh rate. The technology is different from LCDs. Its actually more marketing than anything else (they just want a big number to make it seem better than an LCD, when in fact they’re not talking about the same thing).
CCFL (the majority) LCDs will have muted colors because of the CCFL backlight. Manufacturers have improved upon this with the introduction of the LED LCD. This actually gets the color, blacks, and contrast to really good levels. But you are once again expected to pay a stiff price premium for this feature.
Plasmas are inherently very vivid in their colors. So right out of the box, no extra features needed, you will get a great looking image in regard to color, blacks, and contrast. It is your better overall viewing choice in the current landscape.
I would recommend a 1080p 42″ Panasonic Viera set. Something such as the TC-P42S1. That would likely give you what you want with the best bang for the buck. You could upgrade the contrast and go with the TC-P42G10 as well. That is about as good of a TV as you can own. But it is probably a couple hundred more than the S1. So you can still get an amazing image from the S1 and save some cash.