Not sure if my family will go this year. Kids didn't seem to get all that much out of it a couple of years ago when we last went. The wait for Santa was intolerable (kids were 5 and 2 years old at the time and very impatient) and they were not all that excited to see the mayor and other assorted politicians or unions marching in the parade.
We hung out in front of the Robert Thompson building (Bell Canada office). Crowds were three deep around there, lots of strollers. We drove down, so I can't comment on the bus situation.
Beware the wind around that area--like a wind tunnel around there! Hopefully, you will have a nice day for the parade!
http://www.hamiltonsantaparade.com/intro.html