E2290V- fast response times are typical of a tn panel which although cheap, have rather bad viewing angles
E2370V- ips panels have a very wide (178degree or so) viewing angle. 8bit (panels which are not labeled e-ips) panels also have better color accuracy then other panel types. if 14ms is the MAX rt then it should be okay (unless you want 3d). my old 16ms panel never ghosted one bit.
D2342p-sounds like a 120hz tn panel to me. image quality is probably similar to the first choice you have.
PX2370-you should be looking for dvi or hdmi input. this will give you the best picture. never heard of RGB main input for pc monitors...maybe you mean VGA?
just some opinions based on what you have told me. i didnt research the models myself.
personally i go with nothing less than an 8bit ips panel when i can. these are labeled as s-ips, h-ips or p-ips. e-ips panels are only 6bit. they are only 60hz and have higher response times but i find the color accuracy and viewing angles to be well worth the cost.
as far as backlighting goes: until we see a grid based led lighting system (like some high end tvs are trying out) then you will have either two scenarios. one where the backlight is always on and black always appears to be dark grey and two where the backlight turns off completely during dark scenes making light elements appear darker.
as far as brands go....i've always had great luck with viewsonic professional level products myself.. but i've heard quite a few people mention dell on the forums as well.