Welcome GroovyRudy!
As Rankourabu mentioned you are allowed 3 Full Stop (For as long as you want as long as you return home within 1 year from departure) and you are also allowed 10 Layovers (Stops less than 24 hours). The Aeroplan Website mentiones a maximum of 10 legs (3 full stops/7 Layover) but you can actually push this to 13 legs. And instead of 1 stop you can do an "Open Jaw", this is when you land in 1 city, take a train, boat, car to another city and Fly from this 2nd city.
A 24 hour Layover doesn't sound like much but if their airport is relatively close to the city (I.E. Hong Kong/Bangkok/Frankfurt/Munich/Paris/Rome) you can have a lot of fun.
You will be limited by the MPM (Maximum Miles Permitted), there are tools you can use to figure this out, you can call Aeroplan and ask or post your question on Flyertalk. Once you have your MPM for a City Pair you can start looking for flights.
From YYZ, you can go to Asia via Europe or directly to Asia. Here's an actual valid itinerary:
YYZ-YUL Air Canada
YUL-MUC Lufthansa
MUC-BKK Thai Airways
BKK-HKT Thai Airways
HKT-BKK Thai Airways
BKK-FCO Thai Airways
FCO-ZRH Swiss
ZRH-YUL Swiss
YUL-YYZ Air Canada
Lets say you wanted to book the above, you can't book this many legs on the Aeroplan Website, you will have to call-in and pay the $30 agent fee. What you can do is research in advance. Go to the Aeroplan website and search for 1 Leg at a time, once you have all your flights, call Aeroplan to book them.
Something like the flights above would cost you 75,000 points per passenger (For Economy) and about $900 in fees. If avoid Air Canada, Lufthansa, Thai and instead use Swiss, United, US Air and Aegean you will reduce your fees substantially (They do not have Fuel Surcharges).
Make sure you check if you need any Visas or if there are any passport restrictions (6 month validity, Empty pages, etc) for all the countries you want to visit and also check how far the Airport is from the City as this could make a big difference between Stop and Layover.
I hope this help, feel free to post any questions,
I.T.