I stumbled across some episodes of this show and was watching them and I sat there thinking "Boy, Mr. Wilson sounds like Phil Hartman" I came on here to see who voiced him and low and behold it WAS Phil Hartman. Had no idea he did the voice of Mr. Wilson!
Dragonzord! Mastodon! Pterodactyl! Triceratops! Saber Toothed Tiger! Tyrannosaurus!
Mr Wilson was not voiced by Phil Hartman. Dennis' dad was voiced by Phil Hartman who was doing Saturday Night Live at the time. He would later do the voice of the crooked lawyer Lionel Hutz in the Simpsons in the 90's.
Phil Hartman had a terrific voice but I thought he was pretty bland and uninteresting as Dennis' dad. He clearly had more fun as the bad lawyer on the Simpsons