There are nice beach resorts that are popular with foreigners and you can also do tours. Stick with an organised tour company and you will be fine. Most Ghanians are very friendly but unfortunately its a poor country and there are desperate people out to rob you so leave the expensive watch at home and dont go out with more cash than you really need.
You do have to be careful if you are white because there are criminal gangs that target foreigners, even at Accra airport. If you are staying in Accra ask your hotel to send a car and do not get in any other car or accept any offers of carrying your baggage or you'll not see it again

