It's a nice thing, leaving some of the better stories for a special time. Maybe I might do that with a Doctor a piece for the 50th Anniversary so I have a set of awesome to watch round then. It was certainly nice to finally watch the Key to Time after so long hearing about it, and the same with Sarah Jane's (and the Sontarans) first story 'The Time Warrior', which was a little upsetting because this was just after she passed away. And I actually did the same with 'Battlefield' with Nicholas Courtney.
Nice to hear you're another 90's child because that was when I first saw Classic Who, thanks both to my dad who'd been an avid Hartnell and Troughton viewer and a friend who owned a huge VHS collection of old stories, and naturally being a kid I went for the Dalek and Cybermen stuff first! My cousin who is nine years younger than me calls Nine 'her' Doctor because she was the perfect age for Who in 2005.
You should definitely check more of Five out - I'd rec The Visitation, Kinda, Black Orchid, Earthshock, Mawdryn Undead, The Five Doctors, Warriors of the Deep, Resurrection of the Daleks and Caves of Androzani of the ones I've seen as good choices for Five.
The Dalek movies aren't bad! I actually burst into tears at the wee age of 4 when I saw a Dalek get hurt because I couldn't understand they were the bad guys! But they're decent adaptions of the first two Dalek stories, even if they do take some liberties. Wee Kid Susan is surprisingly adorable and Cushing has enough of Hartnell in his character but also his own take which is surprisingly interesting. Plus Brenard Cribbins (Wilf) is in the second film as a police officer and he's as awesome as ever.