I am a quite beginner for photography and also DSLR cameras.
I searched a bit and found these two NikonD3100, CanonRebelXS.
D3100 is a new one, RebelXS is old but proved.
Which one do you recommend or anything else?
I would recommend that you look at systems and what you want to do photographically. You are not buying a camera here, you are choosing a body that is part of a system. This is not the point and shoot world where once you have made your choice all there is left is a pouch to put it in.
Camera bodies come and go but glass and systems are around for a long time. All this fluff about one body having better this or that at the extremes is for the most part a bunch of fluff, especially for a beginner.
Figure out where your photographic interests lie first. Family, sports, birds, landscapes etc. Second figure out what gear you think you might want to accomplish your goals to start and in the future. Third, look at the various systems out there and find the ones that meet your needs. Finally, go look at the bodies you are interested in and find the one that is the best match for you in terms of ergonomics, ease of use etc.
I have seen newbies buy Nikon D3x's and quite photography a month later because they just didn't like what they got when a Canon rebel would have been perfect. It is the same with all systems be it Nikon, Canon, Pentax, Olympus, Sony or who ever. If you don't like and are not comfortable with what you buy you will not use it or want to use it. Good luck.