My '89 Buick LeSabre stalled on the freeway and other problems

I recently found myself in emergency need of a
car, so I picked one up off Craigslist for $400. It's a
1989 Buick LeSabre. It's older than me. I don't
know what I was thinking.

Yesterday evening I was driving the Buick on the
freeway, and I was kinda pushing it maybe a little
too hard because I was right in the middle of a bad
storm and couldn't see so well due to heavy rain,
shitty (I discovered) windshield wipers, and a
moderate dust storm. I was really on edge and just
trying to get home. So, I was kinda flooring it.

The car stalled mid-freeway. I'm not very
mechanically inclined by any means, but I knew
something was up when I felt the car suddenly "go
slack" and lose power as if it had fainted, and
pumping the accelerator with mounting despair as
I watched the speedometer needle tick downward
seemed to be doing nothing to revive it.

I pulled over on the wet blacktop and shut the car
off. After a minute, I tried starting it again and it
fired up, but it seemed to be struggling all of a
sudden. I steered it carefully back onto the
freeway and eased it down the road for about 3
miles before it lost power a second time.

Exasperated, I again pulled over, waited, and tried
to start the car. It fired up, but stalled again almost
immediately, so I had to shut it back off and wait
for a few more minutes before trying again.

It took a little while, but the car finally spurted
forward and I took my exit off the freeway to go to
my house. I noticed as I traveled down the off
ramp that something smelled burnt. Like burnt
rubber. Like when the vacuum cleaner seizes up
and stinks up the whole house with that acrid, hot
machine smell. I got almost all the way home, and
then the car crapped out a third time. But this time,
it refused to budge. I could start it, but it idled
rough for a second before promptly dying again.
After about half an hour of trying to start it, it
stopped firing at all. It would crank weakly, but
that's it. My dad drove down from another town
and hauled the car home.

So today, I went out to the car to try it and see
what would happen when I attempted to start it. It
does absolutely nothing. It's almost like the battery
is dead, but it's not, and I know that because the
interior lights come on and everything. It doesn't
crank anymore. It just sits there.

I live in Arizona, so the crankshaft position sensor
wasn't corroded by salt water or whatever (I read
that's a common problem).

Any ideas? Please explain it like you're talking to a
5 year old. I know nothing about cars. I don't have
the money to take it to a mechanic, but my dad
knows how to work on cars -- it's just diagnosing
the problem is a pain and so any direction you can
offer will be helpful because I don't even know
where to start.