In no particular order:
1. Indiana Jones
2. Darth Vader
3. The Doctor (Voyager)
4. Captain Jack Sparrow
5. Captain Jean-Luc Picard (well, actually, all the captains.)
6. Al from Quantum Leap
7. Luke Skywalker
8. Harry Potter (...and Hermoine, Ron, Dumbledore, Snape, Voldemort)
9. Hans Gruber (I will always associate the actor with this role)
10. Freddy Krueger
11. R2D2
12. C3P0
13. Princess Leia
14. Marty McFly
15. Doc Brown