My first doctor, strictly speaking, was Eccleston. But I saw two episodes of him, and then sort of forgot to watch it. My first actual Doctor was Tennant.
I've never seen the classic Who...I will have to find them and watch them.
I guess I like the new series - especially the current season - because of the writing, and the nuttiness of Matt Smith. Moffat's a great writer, and he writes really interesting and intriguing episodes.