To understand this saying you need to understand what a lark is.
A lark is a small European songbird which makes its nest in summer in open fields. To attract a mate and to defend its territory, the male lark sings a beautiful, loud, happy sounding, trilling song. It does this by flying high above its nest so, so high that it is difficult to spot the bird even though it is making this lovely noise.
Thus as you hear a lark on nice hot summer days in rolling open country, the sound is associated with summer and happiness.
Thus the expression 'happy as a lark' describes someone 'in their element' perhaps singing away to themselves and obviously very contented with what they are doing.
A lark is a carefree adventure, or a harmless prank.
A lark means a jaunt, an entertaining outing, something just for fun.
lark or skylark
They don't have emotions, if you mean which one will make you happier, only you can answer.
Yes, he seems happier today than he was yesterday
It either means room temperature or fat.
To "sing like a Lark" has multiple meanings in modern usage: It can refer to the beauty or care-free nature of one's singing. However, in criminal vernacular to "sing like a lark" can mean to turn over documents or information to another party, without the knowledge or consent of the holder.
I Am So Much Happier Now That The Rain Is Gone!
I am happy with my parents
yes
nooo
no