ToT was different last year but I don't think it's different this year - I rode it on Friday and I think it was the same as usual. (It wasn't just different during the MHT parties - it was like that all the time last year.)
If your kids are into character meet and greets there are quite a few characters out during MHT - the lines aren't too bad except for Mickey and Minnie and the Princesses. There are quite a few villains out! If your kids want to meet Mickey and Minnie I would do that first. There are also a couple of craft areas. And "dance" areas like the Hokey Pokey Hoedown where they can play with hula hoops, etc.
The midway games are all free and anyone can play - they give out candy for prizes instead of stuffed animals, though.
They added an extra hour to the party last year (and it's the same length this year) which helped a lot in not making us feel quite so rushed. There was *plenty* of candy, especially on the two "treat" trails back at Grizzly Peak and Redwood Creek Challenge. If early in the evening there's lines for the treat stations just keep going further into the park, and you'll find treat stations with shorter/no lines - and as the evening goes on the lines get shorter.
As for other Halloween activities - there are shows at Woody's Halloween Roundup at Big Thunder Ranch, and at Candy Corn Acres (Sunshine Plaza), and those are kind of fun. There are also crafts for the kids at Big Thunder Ranch. In
Disneyland's Town Square the characters are out during the day wearing their Halloween costumes, and their "Candy Corn" festival attire at Sunshine Plaza.
Hope that helps.