We were in Grenada this past Sept. We did not stay at Mahogany Run, but if I ever go back, that is where I would like to stay. The beach it is on, Morne Rouge, is beautiful and uncrowded, not really any other hotels at all, it was my favorite beach. Plus it is just over the hill from Grand Anse, another beautiful beach that is busier, so when you want a little more action you can go there. We stayed at the Calabash which was a beautiful hotel, with great service, but not on as nice a beach, and not within walking distance to any other beaches either.
We found it to be safe, you just need to use common sense as you would anywhere. In general we found the people to be very friendly. The day we rented a car, we put it in the ditch, and every car that came stopped and they all pushed us out of the ditch. So, I would recommend renting a car so you get a chance to explore the island - some of the northern beaches were great, like Bathway, but roads can be a little rough and narrow. A great restaurant, pretty expensive, but wonderful food and service, is Cicely's at the Calabash. We ate there almost every night as it was included with our room, but i heard from others it was the best restaurant on the island (men must wear pants). We didn't find any great shopping. One thing we did which was great was flew to the Grenadines for a day sailing trip through the Tobago Cays. That was a highlight of our trip, I highly recommend it. Have a great trip--we really loved Grenada!