Osu is where some of the most active restaurants and shops are along with a number of expat friendly establishments. There is quite the selection of fast food with Papaya, Steers, and Frankies. International food establishments, including India House, Chinese food, Ryans Irish Pub, and a number of other vegetarian and niche restaurants. The main lane and side streets are lined with stalls selling everything from cell phones to wood carvings, this is a great place to look around and window shop but the prices are much higher. If you have a taste for something western, the Koala Super market is probably your best ticket with a wide selection of international food items. I would definitely recommend that you try some local food, and Asanka locals is a great place to do this in Osu.
All of the above is only on the surface and after living in the area for 3 months in 2005 I have only begun to scratch the surface of the Osu area. Osu had deep rooted traditions as the Ga traditional area. The culture really comes out during the Homoa festival which is a harvest festival that is in essence making fun of hunger. There are some parades and a very active night life during the festival. When homoa is not going on the side streets are fun to explore, but be careful because they are not arrange in any linier sort of way and form a number of circles where it could be easy to wonder in circles.
In the evenings I liked to go down to the beach just to the foot of Osu castle which is the seat of the government, it is very beautiful but pictures are forbidden. On the beach is a little drinking hut where young men in the area would gather and drum the sunset in. To hear up to 20 percussion instruments at a time in this sort of way is amazing. This is not the cleanest beach but it is great for listening to the music and having a great off the beaten path experience.