Uncapitalized "french" is common in "french fries" and is also a verb meaning to remove meat from the end of a bone.
I think English is almost always capitalized even when it means spin on a billiard ball.
(I'm not sure about capitalization of "french" in the context of kissing, but I _think_ it's usually capitalized there.)
(On a side note, Firefox's spellchecker marks uncapitalized "english" as incorrect, but not uncapitalized "french". Weird.)