Alison, I just did a quick search on "blocking" and "ignore" at PalTalk's site. The only thing I cam up with was this:

Q. I don't really care to listen to someone in the room. Can I mute him (or her)?

A. Just RIGHT CLICK on their name and select IGNORE IN GROUP.
You will no longer hear them.

Hope that helps. You might also consider reporting him if he doesn't stop.

There is someone who keeps sending me a request to be his pal and I just keep deleting the message. I don't even recognise the name.

kat