Removing files

I cant remove my file from my ipad.it was save in the usb disk application. I plug in the ipad, start itunes, seect. The app tab, scroll down to file sharing. I lists my apps inistalled aso the document tht i want to remove.there is no check box to click. The buttons are "add and save to". Right clicking does nothing.. Double clicking does nothing. The edit menu doenst have delete. You cant drag the ie to the trash. How to deete this? Help!,..;)

click on the file to highlight then press delete