Across the top where it says File Edit etc, click on "Edit" and then click on "select all" then delete, OR click on "Empty 'deleted items' Folder'. Or click on the first folder you want to delete, then click on the last folder you want to delete while holding down the Shift key, then delete. This way should select all the files between the first and second click.
That should do it.

I have mine set to delete the deleted items when OE closes.

Mikie's plan is great if you are confident. However an easier and safer way is to right click on the 'Deleted items' folder and click to empty the folder. Done.

All the answers/ suggestions will work. Grady

OK, Thanks everyone--I'll try these tips.