+1 on the Tojiro DP, it's pretty much untouchable at the price. As per chef's knife vs santoku, both are useful, but the chef's knife is more versatile. If you were only going to one larger knife it should be the chef's, it will do almost everything pretty well.
The Forschner Fibrox line is also very good for the price: the 8" Chef's Knife is $25,
and the 10" version
is $27. They're sharp out of the box, hold an edge pretty well and are easy to resharpen. I've used the Fibrox knives at work quite a bit and consider them a real bargain.