1. You need to calculate the actual dates. Your stay from 2002-2004 does not count anymore because it is more than 5 years old. Dec'05 to Feb'06 is approximately 2 months. May'06 to Feb'07 is 9 months. Dec'07 to Feb'07 is 1 month. Apr'08 to Dec'08 is 8 months. So as far as I can see, you have 20 months in the last 5 years when you should have 24. That means you have lost your PR status.
2. The expiry date on the PR card does not matter unless it's your first PR card. According to
http://www.cic.gc.ca/english/information/applications/guides/5445EA.asp if you have been a PR for less than 5 years, they will look at if you can still reach 730 days (=24months=2years) in your first 5 years as a PR. If you have been a PR for more than 5 years, they will look at the previous 5 years.