Hello atcheruti
A clarification: In the U.S., a permanent resident card is sometimes called a green card because of the color. In Canada, they just call it permanent residency or PR.
1. Here is the CIC link for investors and entrepreneurs. You can find all of the requirements for net worth, investment, etc. here.
http://www.cic.gc.ca/english/immigrate/business/index.aspI suggest instead that you apply as skilled workers. You should both take the assessment, to determine which applicant, as primary, would give you the most points. Here's the link.
http://www.cic.gc.ca/english/immigrate/skilled/apply-who.asp2. Since you were admitted at one time to the U.S. for at least 1 year, you're eligible to apply to the Buffalo visa office for PR - you don't have to go through Delhi. The Buffalo office is much faster, and would probably have your (joint) application completed in between 18 months and 2 years.
3. It will be very difficult to get a job offer in your situation. Most businesses don't want to deal with the red tape of hiring a foreigner without PR. But if you do, it could fast-track your application.
Personally, I think the best option for you is to just apply to Buffalo as a skilled worker. You could be in Canada in under 2 years.