Welcome to FT
Check out the Aeroplan Top Tier section. Essentially, status miles count toward "status" on Air Canada, which means special treatment, like upgrades, increased baggage allowance, and lounge access before/after your flight.
The miles you earn with credit cards, purchases, etc. do not count toward status - only by sitting in an airplane (or purchasing an unlimited flight pass) do you gain status miles...
See
http://www.aeroplan.com/your_aeropla...s_2008/home.do
You've obviously got lots to read - try hanging out here for a couple of months and you'll learn quickly - I did!