Lenses are no problem as the others have said. I used both AF and AF-S lenses on my D50.
As for shutter life. I believe it is rated to 40,000 or 50,000 shutter clicks. I have almost 17,000 on mine.
In just under 5 years I have less than 30,000 between my D50 and D300. I take ALOT of pictures too. (3,000 on one Disney trip). Unless you go crazy with picture taking, you should be good for quite a few years. Though, with any camera there is no guarantee how long the shutter will last.