If immigration has never actually revoked your PR status, you are officially still PR but as soon as you try to get a travel document to return, they will revoke it. If you managed to get to Canada without attracting attention, you could live in Canada for 2 years and then reclaim your PR status but getting in unnoticed would be hard because you are not visa exempt. You could try to enter with your old landing documents. They may report you and revoke your status at that point or they might just rant and rave and still let you in. I suppose you already had a SIN card? You would need that to work. I have no idea how easy it would be for you to get health care and a drivers license with old landing papers.
Getting a work permit would not be affected by having had PR status and abandoned it. Usually they refuse people because they consider them a risk to overstay while you didn't overstay, you actually left. You would have a problem getting a work permit though if you are still officially PR. If you want to do that, you should talk to the embassy about relinquishing your status.
Hi Leon:
Thanks for your reply, I appreciate it. Yeah, I have a SIN in 2001 and worked in Vancouver for about 5 months. How do I know if I am still officially a PR ? Do I need a lawyer to help me out with this problem ? Thank you in advance.