I used to run an MS setup with an old school MS Natural Keyboard, and a Microsoft Intellimouse Optical v1. It was fine for the 3 or so years I have had it. The mouse was starting to act funny, so I decided just to buy a whole new setup. I recently replaced it with a Logitech Elite Keyboard, and the Logitech MX510. I like my new setup better, but the keyboard was at least 4-5 years old, and the mouse was about 3-4, so it might be just old and worn hardware. The only Microsoft experience I have is on old hardware, and the only Logitech experience I have is on new hardware. I havn't tried any of the newer Microsoft offerings, so its kinda hard to compare such new "equipment" against my old stuff fairly. I hold no bias towards either, both make good hardware, but I vote for Logitech since thats what I own.
Wireless for me is silly. My keyboard and mice are going no where. Cost is higher, and you have to replace the batteries (aside from those rechargeable mice). Overall, its just the extra cost offsets any advantages I would get with wireless (practically none). With the same price, I'd consider wireless, but I'm perfectly fine with my wired setup. The wires don't get in my way at all.
Optical > Ball. No explanation needed.