We're in CO and our last trip was for 8 nights, but eventually it turned into 9 nights because of a delayed flight. We went to WDW (just the theme parks at Downtown Disney), Universal/IOA, and Kennedy, and would have loved more time.
My 2004 trip was 6 nights, but just for WDW. We flew on the red eye from WA. It was enough time to go to the 4 WDW theme parks, plus Blizzard Beach and Downtown Disney.
My 2000 trip was a land/sea package, that I believe was 3 nights in WDW followed by 4 nights on the Magic. We may have added on an extra night to WDW but I don't think so. I don't think we went to all 4 WDW theme parks. Again, we flew in from WA to get there.
I have no idea how long my 1998 trip was. I think less than a week. Also flew in from WA.