Although diz puts one perspective, I've never had any problems in collecting my funds from PayPal, ron.
When you log into your PayPal account (and do it direct, not through the link in the email, just in case!), there is a tab which says something like "transfer funds to bank account". You click on that,then tell them how much you want to move and into which account (in case you have more than one active on PP - e.g. I have a bank account and a back-up credit card on mine). They then confirm on the next screen, and within a couple of days you can usually see the credit in your account. If you look at your PayPal overview, you'll be able to see it's moved from your account too.
I hope this works for you - I've never had anything like a proof of delivery request from PP, so I'd be a bit cautious of that email (unless others can say otherwise).