I would never go for a wireless mouse or keyboard. Those things eat batteries (unless you take rechargeable mice) and don't provide any real useful benefit to me. It doesn't happen that often that I need to navigate my laptop or computer from a longer distance than my keyboard/mouse provides but even then an extension cable would help.
Only time I would use a mouse personally is when the only pointing device on the laptop is one of those silly "eraser mouse" types like the IBM thinkpads are notorious for.
On my Dell, I just use the touchpad. If you turn off pointer acceleration, and jack up the sensitivity a bit, it's pretty easy to get fine control out of. Pointer acceleration is the enemy of accurate mousing, in my opinion.
I bought a wireless mouse for my laptop (simple Microsoft two-button with wheel), and honestly, I think it's not the better option for a laptop. I quickly put it on my desktop box, and started using a USB mouse on the laptop.
My reason was that I STILL had to plug in the mouse's receiver to the laptop (which was about the size of the mouse itself in this case), so I just found it easier to have one simple device with one cord. I did look at the small wireless mice with the receivers that are about the size of a memory key, but that just seems like something waiting to get lost.
I just think it's simpler to get a USB mouse for use when you don't want to use the touchpad on the laptop (or whatever you have).
I love it. It has a slot in it where the usb reciever goes into, and once you put the receiver in it it shuts off thus saving battery life. It also shuts off after a couple of minutes if it is not used. I highly recommend it,
I use the Microsoft wireless intellimouse. Its a desktop mouse but works great for me on the laptop. Has 4 buttons plus the wheel that also does side scroll. It was $15 and the batteries lasted about a year with everyday use. the Reciever is a little bulky but you can hide it behind the laptop. Has over a 6ft range. they do make a laptop version bu i havent used that so i can not vouch for it.