If i was a god...

[i3670]

I would:

Remove every possible disease.

Eliminate death.

Get people back from the dead who have died because of things they didn't cause themselves (holocaust, disease, murders etc.)

I would remove humans who are only selfish, greedy and harmful to others and/or to the Earth, thieves, murderers, rapists, child molesters and all kinds of other useless junk.

Remove possession, so that everyone on this planet could eat, drink and live happily without constant fear.

Those came to my mind at first. But since I'm not God, I can't do anything.

If you remove death than all your other things become meaningless. You don't need to drink or eat if you can't die and murderers will become extinct and thieves won't exist because no one owns anything.

Edit: Also how can you be greedy if everyone owns everything?