There has been a lot written here on this sort of thing already.
I'll post this and then come back to add links to relevant posts by edit later.
That evolution happened has been proven to as great an extent as anything has been proven in science.
How evolution occured has been worked out to a very great extent. However, "proven" isn't something one applies to the "how's" (that is theories) in science.
Creationism (as in young-earth, flood, all life created at once) has been "proven" false. That is easier than proving something true.
To actually discuss this it is necessary to get into some hairy philosophical issues about the meaning of "proof" and other terms which appear, at first glance, to be simple, but are not.