My first choice would be Marathon Weekend, because the spirit of the event spans the entire resort, and there's a distance for everyone. I love how runner-focused it is all week.
My next choice would be the Disneyland Paris Half Marathon, because it would mean a yearly trip to France. The cast members and the multi-national flavor of the event make it special.
I loved the Dark Side Half inaugural course, but I'm not sure about the course changes, and April weather is too unpredictable to make it a regular thing for me.
The Disneyland Half is too hot for me, though I enjoy the crowd support.
And lastly, the Tower of Terror 10-miler was canceled. I'm not broken up about it, because I'm a morning runner and it was too hot and humid for me (surprise), but I loved that the 2012 party was until 4 AM. I think those days are gone for good.