Delete points from point cloud.

I've imported a point cloud from a scanned object. Some of the data is
unwanted. Is there a way to delete individual points or groups of
points?

I know you can do it by deleting rows in the Offset CSys Datum Point
tool, but that's taking forever. You have to find each row in the list
that corresponds to each desired point in the main window. A main
window group select would be very helpful.

Thanks in advance,
Chris Kirchen