Use Views to delete a record from the database
Userpoints can not be deleted, at least not through the UI.

Instead, you need to create a reverting transaction that removes the points that the other transaction added, or the other way round.

The only thing that you can currently do out of the box is building a link that points to the add points form with the username pre-filled, by using that as a token in views. Then you just need to add the points and save.

Everything else currently requires custom code, by e.g. writing a custom action.

Userpoints 7.x-2.x will allow this using bulk operations and better rules integration, but there is currently not much progress on that branch. As in, pretty much none.