I actually thought the parade was alot of fun, b/c the characters are dressed in Halloween customes, also we ate dinner at Cosmic Ray's and if they have Stitch's Dance Party again this year, my girls thought that was a blast, it took us over an hour to get them out of there.
We pretty much skipped the trick or treating, hit a few spots, but they gave such massive amounts of candy at those spots we only had to stop at a few.. My girls loved Goofy's barnstormer, so we walked on and on and on (5 times in a row to be exact with about a 1-2 minute wait!)
Your son looks pretty young, so you may need to do the 1st parade, but if he can hold out, do rides/attractions during the 1st and watch the 2nd!
Also watch for characters - we walked from Toontown to Fantasyland and *poof*

there were the 7 dwarfs & snow white (I was told very rare, but we were told by a CM that night who saw my DD was snowwhite & the adults were the 7 dwarfs, that they might make an appearance) they just did a general "walk-through" in Fantasyland, but it was still AWESOME, my then 3 year old (snowwhite!) was grinning from ear to ear!
Have a GREAT TIME!!
Chip