All you need is a pump and some tire levers. This article is for fixing flats but the process is the same, you just don't need to patch or replace the tube:
http://sheldonbrown.com/flats.html
You can get a set of 26"x1.5" slick tires that will roll smoother than knobbies, they will also help your overall speed. Here is a cheap example:
http://www.performancebike.com/shop/...tegory_ID=5430
If you want a tire that will be smooth on the road and still give you some traction offroad I suggest these:
http://www.jensonusa.com/store/produ...ntry+Tire.aspx
The tread on these is inverted meaning it has pits or pockets instead of knobs that stick out. They roll like slicks on the road but will still have decent traction on the dirt. Not as good of traction as a knobbie but pretty good. I recommend them highly for multi-purpose riding and commuting.