I’m turned off by TV shows shot on video in general. It’s just an ugly, ugly aesthetic. My imperative to watch Doctor Who would be greater if they had made greater use of film.
Then boy will you like Spearhead from Space, the one story to have been shot entirely on film do to union disputes. This makes it the only pre-2009 story that could be entirely remastered in HD without upscaling.
In all seriousness, though, Spearhead from Space is an excellent place to start.
FWIW, Google tells me the show nowadays is processed to look more filmic. I know the Chibnall Era is often cited as being cinematic, but the writing is unanimously panned for most of it so who cares.