Can people change?
Yes. I wouldn't be much of an idealist if I didn't have faith in people and their capability to change.
If yes.. How much and what?
It depends on what the motivation is and what brought about this need for change. I think people can undergo a complete change but in order for this to happen there has to be something drastic triggering it and the resolve to change must be very strong. What can be changed? Everything, I guess. Within reason.
What is staic what is fluid?
Maybe in order to change to happen, everything must be fluid. Or the only thing static is the determination, motivation to change.
Are we stuck with certain things or can we grow and adapt to anything?
Well, I guess we're stuck with our minds, that's the starting point for any kind of change to happen. How open and honest are you willing to be to make things happen. I think we can grow and adapt to anything we're willing to accept. Within reason, of course.
Are some values ingrained and who we are no matter what?
If you think like that, if you think that there are some values holding you back from the change you should be going through, then that's how it's going to be. Your mind is what hinders you.
It depends on what you value as well, and how it clashes with your motivation to change, I guess. How important is the change for you and what are you willing to "sacrifice" to make that change happen. Maybe the change you seek isn't anything positive.
Can experience make a difference.
Yes, it can. It can show you that there are some things that you need to change, that going on the same as usual is not working anymore. It can show you that things don't necessarily have to be the way they are, were they negative or just standing still. Experiencing something that has a great influence on you, either positive or negative, can just open your eyes to possibilities you hadn't thought of before. But it again depends on what you do with the experience, it alone does not change anything, only you can do that.
What about trauma?
Absolutely. That's the most drastic way to open your eyes. And how you deal with it can make you or break you.
Is change just superficial or can we actually shift our core?
It can be superficial, think about all those New Year's resolutions and whatnot, people don't really mean them and they know that they don't mean them, so they're not "real" in a way and most often that makes it ok to drop them after a while.
As I said, everything depends on your motivation, how seriously do you want things to happen and how much are you willing to work for it. Anything is possible, you might also find that the change you desired at first is not what you want some time later on but it can be positive nevertheless. Progress is power.