I use a D3000 with a Tamron 70-300 (I assume you have the AF-S compatible autofocus version)
The image capture is more than fast enough and the autofocus keeps up pretty well but the continuous frame rate is only around 3fps.
I would suggest you get yourself the D3000 field guide book which will be a great help as there are many settings you can adjust, all of which make a big difference.
It really depends what you want to achieve but I'd suggest starting out (under daylight) with ISO 200 on shutter speed priority mode set at 1/800- 1/1000.
This will get you going but don't be afraid to experiment, after all it doesn't cost anything.
You can see a few shots I have taken with this combo on my blog
HERE.