The tram is one block from the hotel and will get you a block or so to the convention center. The tram will also take you to union station and back. You can get buses for other parts of the city at union station.
Using Google Maps I get .7 miles and a 14 minute walk. You could do the first half on the North-South free light rail line heading South and then walk West on 13th st to convention center. Faster and cheaper than finding a parking place, depending on your event.