Wusthof Classic 8" would do all those tasks and more. I have that and a Shun 8" chef's knife. The Wusthof is a little sturdier and what I would use on meat, as I use the Shun almost exclusively for veggies, but the Wusthof does those just fine as well. If you're looking to get just one I would go for this. The Wusthof Grand Prix line is good as well, just do not get their Gourmet line...cheap stuff.
Pretty much the only knives you *need* are a good chef's, a paring, and a serrated knife for things like bread. But I would say I use my chef's knives 95% of the time. I would like to invest in a nice boning one at some point, but I've gotten along fine without it. Most knife sets have some useless knives.