Wow, I live in Ottawa, just can't believe that hockey was ever played in the Aberdeen Pavilion. That place is so small, I have no idea how they ever fit an ice surface and ANY seating in it. Would be nice to find some attendance numbers
According to Paul Kitchen's book on the old Senators, the Pavilion had a capacity of 4000 spectators. No mention of the size of the rink, maybe it was smaller than current standards.
Not pictures, but if you're curious where the old arenas were located I put together this Google Earth map with every current and old NHL arena location. Some ancient arenas that teams played in are still standing, such as Detroit's 1926-1927 home in Windsor and Boston's 1924-1928 rink.
Green = current
Yellow = former, but still in existence
Red = demolished
GE has some satellite photos locations dating back to 1995, where possible I've timestamped the links to show them before demolition. Activate the "Show Historical Imagery" button in Google Earth--it's the "clock" button on the upper tool bar.