Fresh blueberries would be the best choice, frozen is also a good choice especially since all the sorting and such is done for you. I have not tried the canned ones, maybe some one else can chime in on that one.
As far as honey choices go you have many. I just made a blueberry mel with orange blossom honey and tasting it at bottling time showed lots of promise. I would recommend trying to find local fresh honey for your meads and it really does not matter what you use and you can even use a blend of honeys. A great source of information can be found at
http://www.honeylocator.com/. You can research under your state for local honey as well as read about the different types of honey. By the way we have one member who managed to score local blueberry honey for his blueberry mel. He called it Blue on Blue. Keep in mind I have made some very good meads using honey that I bought from Sam's.
As far as how many pounds of fruit per gallon to use, that really is a personal choice as well but 3 lbs is a pretty good starting point. Something you can do to beef up the blueberry flavor is add some additional fruit to the secondary, a pound per gallon and let it sit on them for a month or so. You can even put all the fruit in the secondary and let them ferment that way. The nice part about adding the fruit in the seconday is you tend to get more of the fruit flavor since most of the more violent fermenting is finished and you don't drive off the fruit flavors. I've made mels both ways and it does make a difference.
Something else to keep in mind is how sweet or dry you want your mel. You can drink sweeter meads earlier, the dry meads seem improve and taste better and sweeter over time. I heard it described like this: Dry meads really start getting good at the 3 year mark, at 4 years that are fantastic, and at 5 years they are absolutly awesome.
What yeast yeast to use is another consideration. If you choose to let the mead sit on the fruit in the secondary you'll want to be careful as some yeasts will cause off flavors. A good safe yeast to use is D47 and you'll want to use 2 packs as well as make a starter. Honey and blueberries can be stubborn to start all on their own, adding them together can make you wonder if it will ever start!
Have fun, meads can be challenging but well worth the effort.
VPC