i did find any option to delete a triggered send please let us know if we can delete it. I need to delete a "Triggered Send" in Exact Target under my interactions tab
You can have a triggered send deleted instead of just archived. It requires opening a ticket with ET support & it could take a few days.
As Vjay stated, just archiving it & moving it to another folder is usually sufficient.
Another good option that you can do is to rename & update that trigger to point to a new email if needed.