I think I would prefer episodes from stories we have nothing from, completing stories like Web would use up 5 episodes all on its own while having one episode from various missing stories would at least give us an idea of what each story was like. Probably best to have the first episode as they work best in isolation.
Marco Polo - Episode 3 maybe - 1 takes a while to get to the main story and 2 lacks the Doctor while 3 is quite a busy episode for everyone.
The Myth Makers - Episode 1
The Massacre - Episode 1
The Savages - Episode 1
The Smugglers - Episode 1
The Power Of The Daleks - Episode 1
The Highlanders - Episode 1
The Macra Terror - Episode 1
Fury From The Deep - Episode 1
That's 9 episodes so for the tenth it would be Episode 3 of The Web Of Fear as I love that story and it is the first appearance of the Brig.