I will be travelling soon so I will use it for all sorts of photos

Depending on your budget. About everything, except picture quality, D7000 is certainly better than d5100. D7000 is weather sealed (Keep shooting in rain or snow), has bigger viewfinder usw... About the picture quality, they can do same good. It's just how you take the picture. I prefer d5100, because it's cheaper, so I can buy lens later. Lens are somehow more important than the body.

am an amateur still learning various things - use more of low light and landscape photos - few portraits as well; important features to me are HDR ; d lighting helps; as i usually take 9-10 pics with different ISO and exposure in fine jpeg as i dont like to waste time in much editing after - shoot raw v rarely; i use a d5100 and with 18-55 vr; 35mm afs and planning to buy a 70-300mm vr afs lens - ppl say there is almost no difference in image quality between d5100 n d7000