When i plug in my Iphone I am unable to sync any applications..

When I connect my iphone 3g to itunes and i click on the app tab under my device it is cloudy and i am unable to click any thing.. i have tried deactivating and reactivating my computer and that did nothing.. it actually took my apps away.. this just happened today. Also about a month ago my iphone lost all of the factory installed applications, such as, camera, safari, app store, itunes, youtube... so i have nooo clue what the heck is going on.. i would go to an app store but the closest one is over an hour away and i am a very busy guy.. PLEASE HELP ME OUT!!