(Genre: Just like That)

I think Happy Diwali is the first thing in order. Not just because the festival of lights just passed by, but also because it was at Diwali Puja that this thought originated.

Why are different Gods depicted in different ages (As in "How Old ?") ?

Lord Krishna always shown as a kid or a teenager. Surely he was old enough to be a grand dad at the time of the epic battle.
Lord Rama is always depicted as a handsome young prince. He must be middle aged when he came back from exile.
Lord Shiva is generally Middle-aged. Probably he did not do any great deeds as a kid.
Lord Brahma is the grand daddy of all Gods. Always shown as an old man sitting on a lotus in the limited temples we get to see him in.

Why is it that we don't see a young Brahma or an old Krishna anywhere? The pictures of Gods are just an artist's impression of how the Gods might be. How come all the artists see Rama as a suave young dude and Shiva as a middle aged married one ?

Whatever be the age of the God, the Godesses are always young. (Perhaps, that is why when we see a gorgeous woman, we exclaim "She's a Goddess!!")