well- just to be argumentative..... I would be a little cautious.
take heed of what DandyDon said- stay within yor trainign and comfort level and follow the advice to pick a shop well. Although when I went to cos last year I had cmpleted AOW and near to 100 dives, I am a cautious diver. I went to an op with a reputaion for catering to newbie divers- a big 'cattle' boat with lots of other newbies. My experience was far from safe, or pleasant. I am sure the only thing that kept me from injury was my awareness fo safety factors. they were definately in the 'suit up and throw in' brigade.
that being said, I think I was just unfortunate in my choice of operator. The 'only' thing I would caution newer divers about for coz is to be aware of bouyancy- with the 'live drift' diving they do in Coz you need to be perfectly weighted AT THE END OF THE DIVE to assure you can hang in 15ft without a line to do a safety stop. I had never emptied a tank in my life- so had a few bouyancy probs and felt uncomfotable doing a safety stop in a current. Also carry a safety sausage and use it as the number of boats in the area can make it a little hazardous.
Many hundreds of divers, lots of them newer divers, got to Coz every year and have a blast. I am sure you will love it as most do, just be a little more aware of what is required for a drift dive. Theres a good list in one of the threads above.
As for Coz being good for non-divers, it depends what they want- if they want beach and watersports and shopping, then it is great. I think with a family, it can be one of the better dive areas for non-divers.