1. Landing procedure, you show your passport and PR visa and your proof of funds for a family of 3.
2. Doesn't matter if you drive a car or take a plane
3. Landing procedures and paperwork explained at
http://www.cic.gc.ca/english/immigrate/skilled/arriving.asp4. I don't know
5. You can go and come back same day. It is not mandatory to apply for a SIN. If you ever decide to move to Canada, you can apply for it then.
6. You can not provide a US address but you could arrange a P.O. Box in Canada and automatic mail forwarding to your US address or you can just tell them to hold the PR card because you are not moving yet. If you ever decide to move to Canada, you can get in on your landing documents and apply for the PR card once you have moved.
Once you land, the clock for residency requirements starts ticking. Once you are outside Canada for 1095 days (3 years) your PR status is gone.