When I bought my Mac mini earlier this year, I bought the Apple Wireless Keyboard and Mouse so I could easily control the Mac mini from across my living room.
My experience with these bits of kit has been less than impressive; there’s a noticeable lag when making any input (especially bad with the mouse), and occasionally the keyboard and mouse have to be re-paired with the Mac mini.
My patience has worn out, and I’ve now paired a wired Apple keyboard with a wired Microsoft mouse, connected to the Mac mini via a cheap 3m USB extension cable. The extension cable is usually hidden beneath my TV stand, but it only takes a couple of seconds to retrieve it or store it, and the result is infinitely better than the old wireless solution.
If your room isn’t too big, I’d recommend this solution over a wireless keyboard and mouse. It’s not as elegant, but it’s cheaper and more responsive.