Really sounds like you could use a D50 too.
ISO1600 is very usable, good built in flash.
And for really low light, you could get the 50/1.8 lens for about 99$ (i'm thinking about buying that one too, together with the 70-300g, allready have the 17-55 kit lens) or even the 50/1.4

The site where i learned most basic slr stuff:
http://photo.net/learn/making-photographs/light