Oh no dude, heres what I did when my iTunes weren't launching either.
If your using a windows computer:
1) Go to control panel
2) Add or remove programs
3) Find the iTunes program
4) their should be a box to the right of it, asking whether or not you want to change or remove the program.
5) Click on it and a prompt will come up asking you would you like to remove, change, or
repair program.
6) It will then repair it, then try it...
Good Luck!
-If that doesnt work just re-install it

If you have to go their I'll go more in-depth