It's a couple of years since my kids were young enough to want to watch Tellytubbies but the tune still haunts me. Spongebob is the latest curse.
Luckily we have the BBC in this part of the world which doesn't carry any advertising, and I mostly restrict my own viewing either to the beeb or watch a DVD. I find it kinda funny to watch American programs where the action seems to just stop every ten minutes or so, and then restart with a brief reminder of what was happening before the break.
Trauma wise, I don't think it gets much worse than the birdy song.