Moomba Beach, Eagle Beach - just about anywhere I can wiggle my toes in the sand and enjoy an ice cold Bright
Welcome to the Board xconcepts. Senor Frogs is pretty close to the Raddison as is Gustos (sp). Club Confessions is also nearby (in the same building as Daniel's Steak & Chop house) but I have never been there so I cannot provide any sort of recommendation. Also, just around the corner from the Hard Rock is a place called South Beach; they have live bands most night and is a pretty fun place to hang out. There are not too many "Clubs" so to speak in Aruba but you can find lots of fun anywhere you go.
If you like drinking and dancing, you may want to check out the Kukoo Kunukoo bus too. We went to downtown bars and danced all night. It's a little cheesy at first, but if you go with it, its a lot of fun.
Eagle Beach to relax / Malmok, Boca Catalina & Arashi for snorkeling / Carte Blanche, Senior Frog's, Zeerovers, Sopranos Piano Bar, Kuku Kanuku & The Pata Pata Bar / The weekend flee market.
I highly recommend the Kukoo bus. Lots of partying and dancing. But make sure you have something to eat when you get back. You eat early and with all the partying and dancing you work up some hunger. We grab subs from subway, good late night snack!