In terms of the reliable specifications, they're the same (they might even use the same panel model internally for all I can tell). Do you care whether the monitor has an external power brick? (the Samsung has an external power brick, the Dell keeps the power supply internal) If not, I suggest you go with the one you can get a better warranty on. If that's the same for you, go with whichever is less expensive for you (you haven't specified what country you're in, so I can't determine this for you yet)
I don't think there will be much difference in color between those two - they both use TN panels with W-LED backlight, which is about the worst combination in modern monitors as far as color goes. To get better color, look for a monitor with CCFL (if it doesn't specify an LED backlight, it's probably using CCFL backlighting) or even RGB-LED backlighting (though the latter is scary expensive) and VA or IPS technology. Performance is more difficult to compare, since I didn't find a technical review that actually measured the input lag and response time for either monitor.
Some people like LCD monitors with LED backlight because it is thinner and lighter than traditional CCFL (florescent) backlight. It also uses less electricity and produces less heat. They are all edge lit (at least the ones geared towards the general consumer) which means there may be case where could more backlight bleed along the edges compared to a LCD monitor with CCFL backlight.
In terms of which of the two monitors are better, they both look similar based on the specs. Therefore, the performance should be similar.
By "better in color" are you referring to color accuracy or are you looking for vibrant colors? They are not one and the same. Color accuracy on a TN panel monitor is somewhat difficult to get because TN panels can only truly create 256K color and then uses dithering to blend those colors into about 16m colors. If you are referring to vibrant colors where the colors pops out at you, then you may want to look for a monitor with a glossy screen. Glossy screens are highly reflective though (like a mirror).
Also some LCD monitors with LED backlight may have slightly bluish color that some people may notice, while others won't. This is due to the fact that all LED (a.k.a WLED) backlights are blue LEDs with a yellow phosphorous coating to imitate white. Sometime the imitation is not so good which results in the slightly bluish colors.