Pah! Phooey!
We're born, we live , we die. End of!
If you want to hang on to a dream of being re-incarnated as a butterfly or whatever, then fine, but if you're worried about descending the seven levels of hell because you once trod on an ant, slip the vicar a drink and I'm sure he'll put in a good word for you.
I wouldn't worry about what happens after death; contemplate more the manner of your passing. I'm lucky; I have a dodgy ticker. Once I've had enough, I can just stop taking my pills, and overindulge.

If I go before I'm ready, it will be quick and relatively painless.
My worst nightmare is dieing slowly, in great pain, in hospital, where they think they know what's best and won't allow you to go without prolonging the agony.
I did think I had died last year. I was brought round from heart surgery by a very pretty nurse, blonde hair tumbling out of her cap, milky white skin and rosebud lips, blowing gently on my wrist.
My first words were
"Am I dead?"
I was a bit disappointed to be told I wasn't since this vision of heaven wasn't bad. I still half believed I'd pegged out until another nurse came in brandishing a syringe. Her hiccup while injecting me confirmed I was still alive.
I don't take this stuff, or much else to be honest, seriously anymore.
Here's a nice jolly song about death.
http://www.youtube.com/watch?v=Nffh-ECgoV0