There can be number of reasons why you want to delete the contents of the Filezilla queue. You may want to remove incorrectly queued single items or you may want to clear the queue completely: Here's how:
1) Single right click to clear the single file from the Filezilla queue.
2) Clear all: Right click remove all
Hope this helps if somehow you end up with items in your Fileszilla queue and need to delete them.