I'm thinking you're in the "Reconcile Bank" screen, where you have your imported statements on the left, and the transactions you've entered into BankRec on the right.

Highlight all the transactions from the left (your stmt) that you don't want and delete them (there's no delete button on screen, you need to use the delete key on your keyboard). Then Click "OK".

When you go back in, all those transactions will be gone.