I think the only thing that areas like don mills/ eglinton may have on yonge and dundas is vehicular traffic. Even then, that's only a maybe. Yonge and Dundas trumps it in everything else, particularly pedestrian traffic - which i think is the best gauge when deciding what the "busiest"...
Well i suppose it could be open to debate, but I'm pretty sure Y&D is busier than Y&B in most things, particularly pedestrian traffic. Especially on a nice summer day, I don't think there is much comparison as far as that goes.
56 million people pass this intersection each year...
I'd say even 15 minutes is being too optimistic. Park Lake is not bad if you drive and want to live near the lake and park, but less than ideal for what the OP is looking for.
Perhaps you should read his post again. It should be obvious what he is asking. He pretty much wants an urban area with places like bookstores, coffee shops, grocery stores, restaurants and the like, none of which are within walking distance at Park Lake.
dt toronto geek's suggestion is a lot...