Well, production-wise, I think late 80s early 90s, I love the RGs and all of the Floyd-y
super strat stuff. But, for buying, I voted 80s.
In the early and mid 80s you could walk into a pawn shop and get a 60s strat or Les Paul for $200 or something like that, the vintage overpricing was nowhere near what it is today. Then GnR and those type of guys came out and everyone suddenly wanted old
Les Pauls and other vintage stuff, and all of the musicians were talking about going to pawn shops and getting these sweet deals, then those deals either all got bought up and/or the pawn shop owners got wise to what was going on and started putting higher prices on their guitars. And that still goes on to this day, but not just for nicer vintage instruments, but for all guitars. I went to one last time I was in Florida where I used to go to get gear all the time, and they had a Peavey Tracer ticketed at almost $400, which is completely insane.
So, while we may have a much greater choice today and "shopping" for guitars is great, I think the over inflation of vintage prices (see Nick Coumbe's post) has kind of made actually buying guitars kind of crappy, unless you have a lot of cash - although I will say I have gotten pretty lucky on the quction site that dare not be named. The 80s was where it was at, I think. I just wish I wasn't in still in school and had cash at the time.
That's what I think anyway, I could be wrong...