For me the 70s. I grew up in the 90s, but the 70s was the best decade for comedy. Look at the amount of classic sitcoms, they were. The 70s sitcoms, were brilliant, not every single one, but the amount of brilliant sitcoms in the 70s compared to the 90s and 00s wipes the floor. Last decade of comedy I liked was the 90s, anything after that I hate.
70s had AYBS, Porridge, Open All Hours, Steptoe and Son, Happy Ever After, Fawlty Towers, Rising Damp, Man About the House, George and Mildred, Terry and June ect.
Lots of things there which I loved from the 70s.
60s is second though! Till Death Do Us Part, Please Sir, On The Buses, Steptoe and Son, Dad's Army, ect look at what that decade brought us! Some classic and brilliant sitcoms. The prime of the Carry On's ran through this decade also, which brought us some classics.
80s is a third for me, because it introduced alternative comedy, with The Young Ones, Filthy, Rich and Catflap. I also believe in my opinion, that Only Fools and Horses brings the decade above the 90s on it's own IMO. I know people might be mad about this, in the 90s, there was some great shows, but Only Fools and Horses is in a league on it's own. 80s also had some great forgotten gems, such as Dear John and A Fine Romance. Yes Minister, is a classic example of why the 80s comedy was brilliant also. Ever Decreasing Circles, I forgot to mention and a huge bunch of other sitcoms to come from this decade.
90s comes in 4th place. Some great sitcoms to come out of this decade, but doesn't beat the other 3 above. The sitcoms I like in this decade are Bottom, The Royle Family, Goodnight Sweetheart, The Vicar of Dibley, Dinnerladies, Keeping Up Appearances, Men Behaving Badly, The Brittas Empire and The Thin Blue Line. Only Fools rolls into this decade with excellent form and some amazing episodes.
2000s comes in 5th place, and not a fan of this decade. I despise, a lot of the comedy that comes out of this decade. The Office, My Family, The IT Crowd, The Inbetweeners, Gavin and Stacey, and others. Only things I liked from the 2000s, was The Royle Family, Gimme Gimme Gimme, The Vicar of Dibley and the last of the Only Fools specials. That's it.
2010s comes last. Not much to say, that I don't like any sitcom or find anything that I like from this decade. I don't, and I'd rather watch comedy from the 60s or the 70s.
This could be a bit controversial, but is my opinion, and I do respect others if they view different to me, so please don't be offended by any of my choices.