I was there this past summer, unfortunately just after the Natalie Holoway sitaution in Aruba. I never felt threatened and thought the island was very warm and receptive to the people vacationing there. It's the most "Americanized" of the Antilles in my opinion. I would recommend going to Directors bay and you can dive the tugboat, very easy shore snorkel dive. There is a slight charge to enter the facility but it is a nice area and most likely a nice secluded area for you. There is an old quarantine hospital and a fortress you can "kick" around in and get some great pictures. There is a dive shop, (loosely used term) at Directors bay, but can easily accomodate a dive adventure right there. I would recommend pre arranging it all, just for your ease.
We went to the Ostrich farm and that was an interesting adventure. I would recommend it as a unique trip. Some of the houses in that area look in disrepair but again, the people there were very warm and friendly.
If you are interested, you can tour the Curacao de Curacao plantation where the world renowned Blue Curacao was discovered. If you go, you'll have to buy some liquer. The Chocolate Curacao is awesome by itself as a night cap.
Downtown is very clean. There were a few shops that offer unique dutch doiles (SIC?) and we bought some as gifts for friends and family stateside.
If it's any indication, my family plan to go back again this upcoming year, Lord willing the bank doesn't close on us.
Great vacation spot!