I have seen all except for '96 and '93.  So taking into account I would say that top to bottom I would surprisingly give it to Halloween Havoc '98.  The main event between Goldberg and DDP was excellent.  Sting vs. Bret Hart was good.  Hulk vs. Warrior could've been better, but still was a good match to have booked.  I just remember that whole card top to bottom was good.  My second choice would be HH '90, but the screwed up main event dropped it below '98 for me.  THe best HH match though overall was the main event Thunderdome from '89.  Sting and Flair vs. Muta and Funk is still the best overall match.

I finally saw the '92 Havoc recently, with Jake-Sting, I thought it was quite good.
 
My favourite, though, is still Havoc '91, the Simmons - Luger 2/3 falls match, the debut of Rick Rude, and my favourite match...the Chamber of Horrors!  

1989 and 1990 were the best. I'll give the nod to 1989. Loved the Philly crowd. 1990 had a weaker main event in the ring, though it did have the Steiners-Nastys, Morton/Rich-Midnight, and Horsemen-Doom matches. Still, I give 89 the nod.
 
91 was a mixed bag, as was 92. 1993 was probably the worst, but then again, most things in WCW in 1993 were pretty bad except for the first 5 months of the year.

Quote from SSteward on Feb 1^st, 2007, 11:53pm:

 
Wasn't this the one with Windham coming out as a fake Sting, and getting pinnedy by Sid?

The Best Havoc, as in the one I can watch over and over and NOT get bored is 1990. Between that and Starrcade 1990, it was probably the best booked show of the year, and it had that Steiner/Nasty Boys tater fest.

Had to be Halloween Havoc 89. The angles were so hot leading up to that show, the matches were all really strong, and the Philly crowd was revved up for the show which made it even better. Halloween Havoc 90 was a great show as well.

I'm pretty sure 1989 was the first one, I can't recall there being one in '88

i's say 89 and 90 were the best