Pay your respects for those fallen at the War Memorial between the Lord Elgin and the Chateau Laurier hotels. And step into both hotel lobbys and imagine the decades of history those walls have seen.
Rip down to Chinatown on Somerset and eat some good food. Yangtze is good but expensive but directly across the street and upstairs is Chu Shing. Best food in Chinatown. Dim Sum for lunch will knock your socks offs.
If the 67's are in town, get a cheap seat and watch excellent junior hockey. They won tonight and are leading their playoff series.
Barrymores music hall usually has some great acts but if you've got one night, hang in the market. Lots of beaver,....tail.
The Tulip Festival starts around now and has concerts in the market and Majors Hill park.
Or try this
http://www.ottawaentertainment.ca/about_oec.asp