I have had two ACL reconstructions (same knee) 2 years apart. I learned more about knees than I cared to in the process. My last one was in 01, and it's been solid since. Anyway, you've gotten good info here. The meniscus repair is not that big a deal usually.

My comments:
-Get PT, and most likely the PT exercises will have him on a stationary bike pretty quickly to get back full ROM. [Looks like Wahine said this too]
-check out getting a Polar cub. It is a knee wrap that attaches to a thermos like bottle of cold icy water. All I can say is it is incredibly pain relieving.
-Stay ahead of any pain curve with the meds prescribed.
-If he's got to be off his feet for any length of time, try to do some gentle ROM stretches of the leg, using towels, flex bands, or just by straightening it.
In other words, try not to let it stiffen for too long a period at any time.

Feel free to PM me if you want more info.

Good luck. I have a feeling he'll be back to activity in good time.