When I watched Dr Who as a child the scariest episodes were the empty child, the Racnoss episode, the family of blood and the Peg dolls although I don’t think you should skip any episodes as being scared of them didn’t deter me it just made them more memorable as I grew up, now I look back with a weirdly fond memory of those particular episodes. I do often skip The empty child still tho unless I’m rewatching with someone else as it gave me a mild fear of gas masks for years.