If you're asking whether you have to touch each of the check boxes on the left side to select each message before pressing delete for messages in the trash, the answer is yes. If you're asking if there's a way to select more than one option at a time, then the answer is that you need to go into your Gmail settings (menu button, settings) and check the batch operations option.
After you select that batch operations, blank check boxes will appear to the left of the messages. You can tap each of them individually. As you're selecting the ones you want to delete, options will appear at the bottom and delete will be one of them. After you've selected the messages you want to delete, then you can press the delete button. Then confirm you want to delete them, and you're finished.
Another question on this issue, if you have you phone to syn and you delete all the trash from your google account, will it also delete all the trash from you phone account? That would then make go somewhat faster..