When buying filters, get quality multi-coated ones. A circular polarizer is a good start. Hoya, Marumi, B&W, Schneider, and Nikon all make good filters.
Some folks always use multi-coated NC (or UV) filters to protect the front of their lenses. I don't (though I have one I can use if conditions are bad). It's a personal choice. See the Using Protective Filters - Pros & Cons thread pinned in this forum.