Contrary to what other people have been saying, I've always been able to make (relatively) smooth transfers at NRT, provided I know where I'm going. I think if you planned out your route beforehand and hurried, you could make the connection in under two hours, but I wouldn't risk it. Stay at a hotel near the airport and take a flight the next day. The hotels around the airport are pretty nice, and both they as well as the facilities at NRT provide good opportunities for watching planes (if you like that sort of thing). The Admiral's Club isn't too shabby either.

If, in the future, you arrive in Terminal 1 and have to make a connection to AA, then you could easily get to your gate in under two hours. But seeing as you're going from a JAL gate in T2, I'd really recommend spending the night in Narita.

Enjoy your trip!

Aaron G.