Well...I've never been to Quetico.  I like the BW and alos like to spend my money on this side of the boarder...but I digress.  I think the Long Island Lake area is a very nice area, just as Spartan has previously said.  You certainly have a number of entry point you can use, but for a novice paddler I would not hesitate to reccomend the Sawbill Lake Entry Point.  There is a great outfitter for last minute needs and a cold drink when you come out.  Cherokee and Gordon are both beautiful lakes and I also would agree that Frost is a fantastic place to camp (It just so happens that I think I have the Lake Trout figured out on that lake).

Anyway, that is a great area.  Send me a message if you would like some more info.