1. Jon Pertwee. This never changes, and never will. The rest has changed slightly in recent years, though.
2. Patrick Troughton / Matt Smith
4. William Hartnell / Peter Davison
7. C Baker
8. T Baker
In some foetid dungeon: McCoy
In some deep ocean abyss: Tennant.
As for era... All of Pertwee's run, everything I've seen of Troughton, the pre-Susan's departure of Hartnell, the Pond years with Smith, the Sarah-Jane and Leela years with T Baker (can't stand him but many of my favourite serials are from his era), most of the Davison years... Really, the only periods I simply cannot stand are McCoy and Tennant.