Horner's Spider-Man theme
There is some other good stuff out there, but this one emodies the character just perfectly. It has all the heroism, fragility and wonder you need - a very malleable theme. This is followed very closely by Silvestri's Captain America theme.
Unbreakable is very good too, I agree. Especially the Vaughan-Williams like statement at 2:00
John Powell's X-Men theme is good (Phoenix theme is better, though), as is his Hancock theme. And Brian Tyler's cheesy Iron Man accompanies the character's chutzpah rather well too, I think. Karol