I'm ashamed to admit this but I don't actually like the 'Fork handles' sketch. Maybe it's because it's been seen so many times that it's just lost its appeal to me but while I find it amusing I don't think it's anywhere near the best thing they've done.
Choosing a favourite Two Ronnies sketch would be like trying to choose your favourite child to me (not that I have kids mind you).
It's not a favourite but one that's stuck with me for years was an early musical sketch of sorts where the pair of them are stood round a piano singing with Corbett echoing the last part of the line Barker sang. While they were always being a bit saucy I'm amazed they got the punchline through the censors.
It's been a while since I've seen it so I can't remember the lines at all apart from the pay off but it went something along the lines of.
RB - I saw her by the light
RC - By the light
RB - Of the moon in the sky
RC - in the sky
RB - over that old FAR CANAL
RC - Fancy that?