I think the Villa Rosa is still there but it is not open. Is it an older building set behind a brick wall, right on the shore?

Yes thanks mandyc. Seem to remember it was a very small bay. Villa Rosa was at the back of the bay in the right hand corner as you looked from the sea. As you looked from the hotel front, the bay curved round and out at the left and some building was just starting but otherwise not much there. Behind the Villa Rosa was a lot of unused rough ground gently sloping up away from the hotel grounds.
The hotel only had the bay road in front of it then the small beach.
Do you know anywhere nearby worth considering to stay at?

Villa Rosa is still there, on the Malta education web site it is listed as an English language school.

There are a lot of hotels in the St. George's Bay area - the Corinthia Marina and Corinthia San Gorg are nice, and just up the road from Villa Rosa.

Thanks for that. Will check them out.