autoblog's with good pr domains.good idea?

[mirrorer]

Hello,
i have some pr2 and pr3 domains.I don't use them.It's good idea to start auto blogging with them?Will pr help me to get traffic?
Also i find some pr7 domains,but it seems to be fake pr.Where i can check if pr it's valid?Does google detect fake page ranks?

 

[insider]

Where i can check if pr it's valid?

http://www.domainpagerank.com/