taking photos in low light , wide view

Lens selection is critical for low light photography.  Both Canon and Nikon have great lenses for your listed applications.  The standard kit lens for these is an 18-55mm f/3.5-5.6, which is fine for travel, but if you are looking for very wide for indoor use on a cropped senor body then you will need to look at a much wider lens like the Tokina 11-16mm f/2.8.  One important thing to consider is that when purchasing a cropped sensor body you will need to use a multiplier when choosing a lens (1.5X for Nikon and 1.6X for Canon).  Example 18-55mm on a Canon is actually 29-88mm perspective.  I consider wide angle to be wider than 35mm, normal ~50mm, and telephoto narrower than 80mm.  For portraits the kit lens will be OK, but you will get much nicer results from the very cheap "nifty 50", which is a 50mm f/1.8.  This lens on a cropped sensor is in the near telephoto range and the large aperture will give you nice background blur for ~$100.