If you want to delete threads, just click the "you can moderate this forum" link at the bottom right and it will let you pick them a page at a time.
Bare in mind that deleting will affect the post counts of those that have posted in the threads (pruning doesn't)
"So Long, and Thanks for All the Fish"
phpBB Useful Links: Knowledge Base | Userguide | Forum Search | MOD Database | Styles Database
My Links: Blog!