I think that these are both the worst two ways to die, but I think drowning.
Because it must be horrible feeling yourself going down and gradually, slowly dying. Whereas, although burning would happen slowly, i think that the actual death would actually happen quite quickly. Not that I'd know though.
I'm scared of the open ocean, but I'm also incredibly scared of fire, after an incident with a candle when I was 7.
I've heard that from studies that scientists have done, drowning is like falling asleep because the oxygen can't reach your lungs, let alone the rest of your body, so you start to fall into a coma. They conducted these tests on animals though, so...yeah. Burning would hurt a lot worse though, obviously.
Well, I was about to drown one day, and it's not painful. First, you feel a panic, but then you just stop breathing slowly, your moviments are slowed and you have a calm death without any hurt (I didn't die!). Burning is more painful. You feel your body heating and your flesh burning. At least I think it's like that. If I had to choise, I would pick "Drowning".
BTW, I dream about burning lots of times. And it's always painful!
Really, it would be burning. From the many crime dramas I've watched, the people who run around screaming while on fire look to be in more pain than those who briefly struggle for air before losing conciousness and dying.
Drowning. If I were burning on a stake, per se, I'd go from wanting to get the hell away from it to gripping it and wanting to stay near it. Drowning can make you feel numb and make you go unconcious, and if you go unconcious then you won't be able to see the ones you love. At least burning on a stake you could see them and know that they're okay.
Actually, personal experience has nothing to do with it so most of your answers are invalid. Burning is not the most painful way to die because yes, it does hurt, but after your nerves have been burned through (which I doubt has happened to most of the ones who decided to answer this question) you can no longer feel any pain. With drowning, you can feel every drop of water entering your lungs replacing the air that was once there. Your lungs become crushed and there is literally no way to breathe. (which I also doubt has happened to most of the people answering this question-otherwise you wouldn't exactly be answering.)