Personally, I'm not a fan of the MCM expos, I find them a bit tacky but there's usually loads there for kids. I went to the Manchester expo in 2011 and had seen everything within about an hour. There were events on at various times but I just took the opportunity to catch up with folk I hadn't seen in ages.
I much prefer ThoughtBubble in Leeds - loads more events and talks, loads more traders plus there's cosplay stuff on all day. Less commercial and more fun than the MCM events, IMHO.