Both shows are funny I have valued both since they came out, The family guy flashbacks are and always will be funny, Some dont always catch on fast enough, they may be crude at times, But still enjoyable,
The Simpsons in it's prime was funnier than Family Guy and seasons 4-8 are perhaps the greatest things to ever happen to TV, but the show now has redefined "jumping the shark" and can't even muster a single laugh from me for an entire episode. It's depressing in it's current form.
Family Guy is really funny and at the moment is funnier than The Simpsons but even FG is losing steam. Still, stuff like The Superfriends opening from last week's episode, the Disney drawn universe from the week before along with chicken fights and the like make it overall a very enjoyable show that has a more uniqe oportunity to go all out on spoofing and imitations (like Blue Harvest).
Futurama is also fantastic as is seasons 2 and 3 of Spongebob Squarepants ("Night Shift" is one of the most amazing things I've ever watched on TV).
I like The Happiest Millionaire. What's wrong with that?