If you are sick you should:
1) Not fly. In the winter (cold and flu) season, there are more germs being recycled through an aircraft than you'll ever find in your typical pediatric sick ward. Besides, the pressure changes wreak havoc on your sinuses.
2) Take enough decongestant/Nyquil that you are not annoying to those around you.

As for the kids, I actually enjoy sitting next to UMs on flights! Their enthusiasm and excitement (and even nervousness)reminds me of a time when air travel used to be something special for me, too.