Dolby Digital Surround Sound on Mac?
I've been looking into getting a gaming headset for a while now. I am looking into the razor chimaera 5.1 wireless with dolby digital surround sound. I was going to connect the wireless base station/receiver to my mid 2011 21.5 inch iMac via an optical connection (using one of those cheap converters on amazon) because I know that the standard 3.5 audio jack only exports stereo sound. If I did that with this headset (or with any other 7.1 or 5.1 surround sound headset), would I be able to play games, watch movies, and listen to music (iTunes) in dolby digital surround sound? I have heard that mac os doesn't support dolby digital surround sound. Since it doesn't, is there a way to get surround sound to work on mac os with a surround sound headset? Also I will be using it to play some games such as skyrim in windows 7 via bootcamp. windows 7 supports dolby digital surround sound right? Any help would be appreciated, I am no audio expert.
iMac (21.5-inch Mid 2011), Mac OS X (10.7.2), Intel Core i7