The distributor rotor is geared to the camshaft, which is in turn connected by chain (TC) to the crankshaft, so really you have two places you could be off a tooth or two. I would agree with kewlynx, start by checking the timing chain.

I would set everything to TDC and start at the bottom and work my way up, verify that the crank is in the right spot (pull a spark plug and look in to the #1 cylinder, you should see the piston at the very top when the crank shows TDC)

Then check that the cam is in the right spot, it is very possible that you are one or two teeth off on the timing chain which would let it fire, but not run (sometimes).

Then Check the distributor to make sure it lines up with everything else.

If nothing is off on any of those it doesn't hurt to check the valve clearance, but they would have to be pretty far off to not let the engine run at all. Also, never hurts to check all the EGR stuff on the back of the head, I have definitely forgotten to bolt the EGR valve back on and then not been able to start/idle the engine.