My launcher will not respond and wont ever open up the actual MInecraft application.

When I start up minecraft the first part of the launcher will load but once it gets to the "Mojang" title page where minecraft loads it will stop there and it will say "Not Responding" and it will do nothing more than that and I even tried waiting more than an hour for it to load and it still doesnt load to the actual Minecraft application, I have already tried taking it off my computer and redownloading it but it still doesnt proceed to work. I need this addressed as soon as possible please and thank you.