As noted, they're doing a 50th anniversary series, focusing on one Doctor each month. January was William Hartnell, and they showed The Aztecs. February was Patrick Troughton, with Tomb of the Cybermen. March will be Jon Pertwee -- I'm going to place my bets on Doctor Who and the Silurians as the episode to show. April for Tom Baker (my guess: Genesis of the Daleks), May for Peter Davison (any guesses?), June for Colin Baker (again, I'm stumped), July for Sylvester McCoy (guessing The Curse of Fenric), August for Paul McGann (no options here, it must be the "TV movie" they made for Fox), September for Christopher Eccelson (The Empty Child/The Doctor Dances?), October for David Tennant (Silence in the Library/Forest of the Dead?), November for Matt Smith (The Pandorica Opens/The Big Bang?).
That leaves the December special to focus on the new 12th Doctor...
As for the lost episodes... it is indeed tragic, but many of the archived film prints were (inadvertently) sent to the furnaces. Some have been reconstructed from other sources (mostly prints that had been on loan to other stations, I believe), much several of the Hartnell and many of the Troughton stories were lost permanently.
30th anniversary of Doctor Who had “History of the Police Box.”
http://www.youtube.com/watch?v=3avd8xwzzCk