Thank goodness for ranting rooms else I would be booted from the site as #1 spammer. XD
I started off Doctor Who seeing Ark in Space, so for a while Tom Baker was my favorite Doctor. I loved Arc in Space, Pyramids of Mars, Masque of Mandragora, and many others. I liked his humor, his companions, just a lot to like.
Then I saw Pertwee. Although Pertwee's second season can be a tad hard to watch one after another (too much Master overload), he quickly became my favorite Doctor for many reasons. First and foremost, the Brigadier. Unit in general, Sargent Benton. The Master as Delgado, Bessie. I liked his dry humor and his wardrobe. I liked his Venusian karate. Joe Grant is one of my favorite companions being one of the few who started off nearly worthless "I'm here just to shine your vials and make you look smart" to sneaking around Dalek bases and being highly competent by the end.
One of the biggest difference between Pertwee and Tom Baker for me came down in the writing. Inferno was one of my favorite serials in Doctor Who because the story really felt complete with the seventh episode. Many of Tom Baker's serials like the Invasion of Time and many of the 4 parters always felt a bit incomplete or rushed at the end and I never really got that feeling during Pertwee's era. This was one of the deciding factors for me.
I saw all of Troughton's existing episodes first and thought he was so-so. I very much appreciated that he could get me to laugh in even his lesser episodes. It wasn't until I started watching the missing episodes that he was cemented as my favorite. Power of the Daleks, his first serial, he just walks into the role amazingly well. While many actors had to spend time adjusting such as Baker in Robot, he just was spot on from the get go. The serial was also written by Dennis Spooner with a lot of great humor. Victory of the Daleks is a poor man's rehash of this episode, they didn't get Spooner to write the new one. XD In all seriousness, this is my favorite Dalek episode in the show. The following season came the Wheel in Space which became my favorite Cyberman episode. My favorite serial of Doctor Who is the Faceless Ones which also falls in Troughton's first season.
Jamie was an awesome companion. Zoe was okay. Troughton, in my opinion, is like the missing stooge. He's got such great facial expressions and slapstick mixed in with his dialogue. He constantly worked with the writers on the scripts and it shows. His first two seasons are very well made and its a shame that they are missing. His final season, however, was a bit of a let down. Tomb of the Cybermen was descent, the Seeds of Death was alright. The War Games I liked but is indeed a long long episode.
Hartnell did not become my fourth favorite Doctor until around this time. (My favorites go 2nd, 3rd, 4th, 1st, 10th, 7th, 6th, 11th, 9th, 8th, 5th). His first season was hard for me to watch. While I did enjoy Marco Polo, The Keys of Marinus seemed to never end. It wasn't until his second season, Planet of the Giants, the Rescue, The Web Planet, the Time Meddler and this third season the Myth Makers, the Dalek Master Plan (his meeting with the Meddler), the Celestial Toymaker, the Gunfighters (bar the singing), and the Savages that he moved up above David Tennant. Tennant is a good actor, but he has so many many miss episodes and one of my least favorite catch phrases, "I'm sorry. I'm so so sorry."
For Colin Baker, I liked the Two Doctors, the Mark and the Rani and the Trial of a Timelord. His first season had many miss episodes for me though.
Sylvester McCoy I liked some of his episodes. The series quit taking itself seriously and started allowing comedy to override plot points because even his best episodes had fundamental problems. On the other hand, he got Paradise Towers, Delta and the Bannermen, and the Happiness Patrol which is 25% of his tenure. Good actor, I had no problem with him. Even in Paradise Towers where everything was dissolving into a puddle of illogic, McCoy was the only person whom which clarity showed during the entire serial. I have no idea how he pulled that off. When he came in, things started making sense, when he was off screen, goodness help the audience. XD
Si-Fy and Fantasy, that is where my heart lies. To Doctor Who and its 18 years of brilliance, still waiting on the 50 yr anniversary!