Whoa! This is a tough topic, too! One us Animorphs fans can't help but wonder when falling upon.
I think my teenage-self would been totally reckless, genuinely trying to be smart and brave inspite of his outrage, but ultimately naive and not knowing what he was in for, totally. As a result he WOULD most likely have ended up killed or worse... caught. For I WOULD HAVE NEVER been able to live with the knowledge of my bro or my sis or ANYONE close to me being ONE OF THEM. Not if I COULD do something about it.
I would have done SOMETHING...
Today, I don't have the same energy and have more at stake. I would suppress my negative emotions and keep them in check a lot better than in those days. I would go about a lot more subtly and never make a move without any certainty. It would take time and patience acquiring as much info as I could, but always meticulously devising and re-devising a plan that would give me circumstances to have 3 days by myself with that Yeerk, starving that Yeerk out of his or her head. I would proceed pushing to relocate my family and I elsewhere remote overseas or something.
Having read the entire series, I know that a lot more falls into the shades of gray though. I can't picture them being voluntary, but you know...
Definitely would not let them eat ANY sort of oatmeal. Don't care if it's only the instant maple and ginger type. Better safe than sorry.
And I would push it even further, by making friends with some Andalite that is tripping the Earth and talk him into taking me to the Yeerk Homeworld and let me acquire a Yeerkbane Vanarx, come back and eat the bloody thing straight from their head. PS: Not that I would know one exists.
Awesome topic!