New York--Whew! Boy, am I ever glad the prime-time TV season is about to enter its year-end climactic phase. All three networks have been drumming out new programs at a whirlwind pace, try ing hard to placate viewers tastes and squeeze out an extra Nielsen point or two--which translates into increased revenue and prestige. By June, CBS, ABC and NBC will be screening many of their unused pilots, an occasional summer tryout series, second-run movies and, of course, a helpful serving of series re-runs, which are more important than you think. Re runs give most people an opportunity to sample other shows which may have in terfered with their regular viewing habits. Which were the best and the worst series of 1980-81? The envelope please BEST "Dallas"-- Because this is actually a soap-opera gone prime-time, new character additions pivotal to plot development continue to spur interest. Nice going Lorimar Productions and CBS. "Soap"-- Some people think it's too racy. "Soap" is tame compared to "Number 96," which tried so hard to copy the "Soap" formula. The series features excellent writing and acting, and somewhere in the show there's a message for everyone. "M'A'S'H"--What can one say about this series that hasn't been said already? I do get the feeling, though, that 1981-82 will be the last roundup for Alan Alda's boys in O.R. "The Jeffersons"-- it almost expired a year ago, but this long-running series picked up a head of steam during the summer re-runs and then kept right on going. "The Jeffersons" also should be getting more ink because it's the most successful black-oriented series since "Sanford and Son." "Dynasty"-- ABC's own prime-time soap has everything going for it, despite its mediocre ratings. Remember, "Dallas" didn't do all that great its first time out either. The excellent cast and writing staff can keep this show alive for years to come. "Bosom Buddies"-- I'm amongst a small group of people who think that "Bosom Buddies" is the best new sit com to hit the airwaves in a long time. Peter Scolari and Tom Hanks are in stinctive actors, while Donna Dixon, although far from a polished actress, has the look of a typical Hollywood sex sym bol--only a lot smarter. "Hill Street Blues"-- The most critically acclaimed series of the year. Unfor tunately the ratings haven't matched the reviews. But NBC will find a new slot for the police show during the summer to in sure its survival "Charlie's Angels" are about to expire. Dan Travanti and Veronica Hamel of "Hill Street Blues " WORST "Freebie and the Bean"--Another ex ample of a TV series cuUed from a hit motion-picture that just didn't work. "Number 96"--A poor excuse to show America how our morals are going down the dram. Although "Number 96's" amoral residents may have been based, in part, on the lifestyles of residents at a Marina Del Rey, California condo, it isn't representative of what the whole country accepts at this point in time "Charlie's Angels" It just outlived its usefulness after five years Oh, it's fun to look at the girls, but hey. it's the same old plotline every week. "Gangster Chronicles"--"The God father" told us how the underworld operated. TV certainly doesn't have to give many of its younger viewers any other ideas "Flamingo Road"--A great concept that never really panned out because of anemic writing and poor casting I still think there's hope for the show, but it would take a maior overhaul to bring NBC's prime-time soap up to "Dallas" and "Dynasty's" caliber "Aloha Paradise"-- I enjoy watching Debbie Reynolds and Bill Dailey, but those gosh awful rewritten "Love Boat" and "Fantasy Island" scripts can make somebody go coconuts. MEDIA MONITOR By STtVE K. WAL2--TELEVISION WRITER The best and worst of the '80-'81 season