Moving to Canada

I am an American engaged to a wonderful Canadian woman. Can I cross the border with all my stuff and live with her for a time without having a residentency status? I believe that Americans can visit for up to six months at a time, but will the border stop me if I show up with all my stuff? Or can I just say I am taking an extended vacation with my fiance and all will be okay?

Also, can I work in Canada without a resident's status? Or would I need some sort of sponsorship from a Canadian company in order to stay for extended periods?

Lastly, I know Canada has a form of socialized health care. However, can people have private insurance and go to private practice doctors, or do you have to use the health care the country provides? If they can, how much is private insurance policies there (roughly)? I have some health concerns (nothing that will stop me from being allowed to immigrate to Canada) that require me to stay insured and will require me to see doctors regularly. I have heard little except horror stories of the health care system in Canada. Hence the reason why I would like to maintain private insurance if at all possible.

Any help or tips anyone can provide on these topics will be greatly appreciated.