The series I did last week on improving productivity in Gmail, prompted a couple questions from y'all! Good. I love answering direct queries that I know will get used.
"How do I quickly empty a folder? For instance, my "Deals" folder has 1000+ emails in it. I want them GONE. Do I have to check each one and then delete?"
You can select all of them quite easily. Walk through the following screenshots with explanations. Also remember that when in a Label (folder, if you insist <grin>) that you can search within that label to pick out just those emails you wish. For instance in the first screenshot below, look at the search box. I can go into that box and add "youtube" after the label name to just find the emails containing youtube in this particular folder. At that point, I can follow these screenshots and delete all the youtube related emails found with this label containing the "youtube"