When I die what will happen?

I'm not afraid of dying; its a completely nature part of life, but I am afraid that after I 'leave' people will just forget about me. Maybe they will come to my funeral but what happens next? Do they just send flowers and be done with it? I don't want them to be mourning over my death, but I just don't want to be forgotten. I wan people to be happy when they think of me and laugh at all the good times we had. I don't want them to be sad I just want to be remember.
Then the bigger question: Where do we go?
I was raised in a christian family; We were taught that when we die we go to heaven or hell.
In heaven god will be there to welcome you back, in hell you will burn for eternity with know way to escape.
Now that scares me. We have no way of knowing whats going to happen when we die. I want to be in heaven but what if I make a mistake and end up burning in hell for eternity? I don't want that. And how can god just so easily turn away from something he has created and send them to hell? I don't know but maybe death does scare me more than I though.
I know what I said at the beginning completely defies what I just said and people say you shouldn't be afraid of death you should welcome it but I don't know... it's just something about it that leaves me unsaddled. I guess I'm just confused. But you never know.