the skydrive app on Lumia 800 does not work one will always get a permissions problemYou can email PDFs to yourself. And there are several Marketplace apps to move file from your PC to isolated storage on your devices. But all you can do with PDFs is view them. No way to email as an attachment.
An alternative is moving PDFs to Dropbox or SkyDrive, and sending links in emails. Several ways to view files in those Cloud locations.