I would say go donate something if you really won something very big! What's a few dollars to give to charity when you win something from gambling. It's easy money and giving a bit of it wouldn't hurt you. Just donate if you have extra. But, if you need it to cover some loses or pay some expenses, then save yourself first before anybody else.
I would say its not really wrong to donate even those money came from gambling as long you have the passion to donate it to charity it wont really matter since you didnt do anything illegal and that amount you gain is came from your luck and theres no bad thing involve.Dont listen to those people who said its wrong and remove the feeling of hesitations inside you.If you want to donate then do it with all your heart and without thinking twice.
I agree with these suggestions. Donating to charity is a noble act and doing so will make you feel good and enlightened. Not to mention that you can make someone happy too when you donate. But just donate what you can and don't over do it. If I did win something big, I would also donate some. It's just that I don't gamble too much.