CONTAINS SPOILERS, BUT IF YOU DON'T KNOW HOW THESE THINGS WORK OUT BY NOW THERE'S REALLY NO HELPING YOU
"Which is the best of the Friday The 13th series?" is a question for which I don't have a consistent response. Obviously the original has a claim, as it was the first one which came out of nowhere and set the template rather than followed it. I always used to like Part 2, though a recent rewatch proved slightly disappointing. Part 3 is probably best seen in its 3D theatrical incarnation, as the constant poking of sharp objects into the camera lens looks a little silly on home video. And though no-one else seems to like it (no doubt due to Jason not actually being in it) I have a soft spot for Part 5, though that's most likely because it was my first Friday The 13th in a cinema, and I was the only person in there, and not because it's actually a great film.
For some unaccountable reason I didn't bother to see Friday The 13th: The Final Chapter at my local cinema, when it turned up on a great double bill with My Bloody Valentine, and I eventually saw both films on their VHS releases. This is actually Part 4 in the series (though Part 4 doesn't appear on the film itself), and is certainly one of the better episodes, partly due to its slavish adherence to the recipe and partly due to its insistence on slaughtering almost everyone in the movie, even a passing hitchhiker who doesn't even get any dialogue. Jason Voorhees is now officially dead from the end of Part 3 and is carted off to the morgue, where he promptly comes back to life, kills the morgue attendant and his idiot girlfriend, then heads back to the woods where a bunch of partying teens have pitched up for the usual tedious shenanigans.
Clever, innovative and unexpected it certainly isn't, but it's perfectly well put together thanks to director Joseph Zito knowing exactly what he's doing (he also made the terrific campus slasher Rosemary's Killer), and Harry Manfredini's shrieky-stabby score is again as much of a musical signature as John Carpenter's remorseless Halloween theme but much more musically exciting. Toss in the inevitable T&A, a now-legendary Crispin Glover dance sequence, and enough of Tom Savini's splattery death effects to justify the 18 certificate (though perhaps too much for the ratings boards and not enough to keep the fanboys happy) and you've got a perfectly adequate slasher movie. It's nothing better than perfectly adequate, but it's never boring, it does its job and doesn't waste much time about it.