The ONLY place in the parks where bubbles *would* bother me, is in line....because in line you don't have the choice to move away from them if you wanted to, ya know? Well...I guess it would also bother me if we were sitting down to eat, and kids were blowing bubbles close enough that they were popping near our food.
Fortunately, I've not had any problems with my 4 kids complaining of boredom in lines, but that's probably in large part due to careful planning....we avoid long lines like the plague. Are you already considering utilizing FP and early arrival strategies? For us, it probably makes the difference between a really fantastic day with no whining kids...and what would likely be a day I would give up and just leave early because I can't stand to *listen* to whining kids (LOL!!!)
The only ride we can't avoid a long line for is Toy Story Mania...and we usually skip it (but that has more to do with feeling like it's not really worth the long wait). Other than that, we almost NEVER spend more than 20 minutes in any one line, and the vast majority of the time, our waits are between 5-15 minutes. Due to that, my kids never even have a chance to be bored (and seriously, if one of mine said they were "bored" at
Disneyland...I'd probably lecture them on how privileged their lives are compared to most children around the world, and then happily offer to go home early so that they could be less bored cleaning their rooms and doing yardwork, and they probably know that about me, so even if they *have* been bored while there...they've known better than to mention it to me

).
Hope your family has a fantastic time!