vBulletin? God, please, no.
vBulletin is the epitome of featuritis. Commercial isn't neccessarily better, commercial is just more expensive.
What's next? PHPNuke? Geez.
As for PayPal funds: As far as I know PayPal supports European bank transfers, but only via the Add Funds option and I also think you can't "validate" a PayPal account via bank transfer.
PayPal supports German bank transfers and thus I don't see a reason it shouldn't support European bank transfers via IBAN and SWIFT-BIC (which every German bank account usually supports).
Note that PayPal has rather American rules about who can run a business with it and thus it may not be used for sites which display FFN or other things Americans could base a sue on (probably including hot coffee and Michael Jackson).