My 2000 mercury mountaineerjust died?

My mountaineer was running..stopped to
get gas and it wouldn't start back up. Wont
even turn over, but the lights come on. Got
towed home. Gonna check battery and
starter to begin with in the am.. But I saw it
might also be timing chain? I don't think its
the alternator, and wouldn't turn over with a
charge, so I don't think its the battery either. I
also had an issue one time where I had to
jiggle the gear shift into park so it would
start. Is that a fuse or switch issue maybe?