Not necessarily five "buildings" but certainly five attractions:
- The Old Montreal area
See http://www.vieux.montreal.qc.ca/eng/localia.htm
Have lunch/dinner here. While here, visit the Notre Dame Basilica, and the oldest church in the city, the Notre Dame Bon Secours. The Museum of Archeology and History is in this sector.
See pictures in: http://www.vieux.montreal.qc.ca/tour/eng/0cartea.htm
If in summer, take a boat cruise on the St. Laurent river.
Enjoy the view of the "Habitat 67"
http://archives.cbc.ca/IDC-1-69-100-535/life_society/expo_67/clip8
- The biodome is absolutely a must visit
- Stroll down Rue Ste. Catherine and take in the ambience, visit a bar or two on Rue St. Denis
If you can, time your visit to coincide with the great Montreal Jazz Festival - YOU WON'T BE DISAPPOINTED!
http://www.montrealjazzfest.com/preFIJM2006/accueil_en.asp
If you have time, drive around the entire island - you'll get a taste of the differences.
Well, that should be enough to start.