Around Perpignan is great. If you stay south of there, near Collioure or Argeles, it's easy to travel into northern Spain too.
Collioure is very pretty, very busy in summer but nice safe beaches - one sandy, two pebbly - lively, little independent shops, boat trips, music etc.
Argeles is more seasidey, less quaint. There's a water park nearby which is fun.
Slightly inland, Ceret is a lovely arty town. Fantastic market on Saturday mornings.
Lots of little art galleries, museums in the area. And some stunning castles like Peyreperthus to visit in the Tete valley. Great walking and cycling area too.
You won't find any big hotels; tourists tend to self-cater, camp or stay in small family-run hotels.
It's Catalonia so there's quite a Spanish feel to the area. It was actually part of Spain a few hundred years ago.