PR Status dilemma (URGENT) with a US born child.

[PRSeeker2011]

Hi Everyone,
I have the following situation and I am in desperate need for any help/advice.

Situation:

I landed in Mar2008 with my family (spouse and US citizen daughter) and stayed for a few days.
We couldn't move to Canada for variety of reasons beyond our control and I continued to work in US.
I have another child (US Citizen) who was born in 04/2010 and we didn't apply for PR for him.
Now, I want to move to canada with my family.

Questions:
Can I still move to Canada with my family since I longer have the required 730 days of stay ?
Can I stay in canada until the validity of my PR ?
What issues am I going to have at POE and any advice on how to tackle them ?
Is it preferable to go by air (since there are automated machines which lets u in by scanning PR card) or travel by car ?
What if I say I am going to visit my friends and continue to live in canada ?

Any help/advice is highly appreciated....Thanks a ton in advance.