kendiggy

I have a 1996 Accord EX, 4 cyl w/auto tranny, close to 107,000 miles.
About a week ago, I noticed that when I was climbing a hill at around
60 mph, the transmission was slipping a little bit. It seems like it is
trying to downshift to third, but I wasn't giving it enought throttle
to actually downshift, so it was just slipping. Reminded me of when you
have the gear selector in the wrong spot and it won't fully go into a
gear.

First thing I did was check the fluid level, and it was full and didn't
smell burnt. So now I'm a little concerned and I'm hoping there's
nothing wrong that will require replacing the whole thing. I'll admit
that we weren't able to do all of the scheduled maintenances on it
(insert starving student sob story here), and I'd really like to know
if changing the fluids and replacing tranny filter could help. I don't
have any other problems with it, and it's strictly when I'm at the low
end of the 4th gear range.

I've been reading about needing to use Honda ATF, which I'll go pick up
before I do the change. Can I pick up a filter for it at NAPA, or where
ever, or do I need to order an OEM replacement from Honda?

Thanks for the help. I'm hoping I can get a few thousand more miles out
of this before I buy something new!