I would suggest you did what we did and get a local guy, who is an expert in this stuff, to visit you and your wife and explain all of your options. The guy we got was recommended by a few people we know and he only does the Medicare options and supplemental insurances.
I think the plan I chose is called Medicare G. I have A and B and D and for my supplemental I have Cigna. My total out of pocket expense/deductible is $240 per year and I pay $194 per month for my Cigna supplemental.
I couldn't be happier and it's the best insurance I've had since I was in my 30's.
In order to get the supplemental that I have with no preexisting conditions can only be chosen without a full medical statement prior to reaching the age of 65. Once you miss that window you will have to answer a questionnaire and list your full medical history along with all the preexisting conditions.
Maybe DTB can help you with this stuff since that's his business.
No way would I ever attempt to figure all the options out on your own. Get an expert to help you.