Payments using paypal and credit card

I'm intending to sell a product online.
Sales page and copy writing i can manage.
But for the payments options, i would actually want to offer my customers two payment options only which is credit card and paypal.
I'm thinking of using Paypal merchant services as the payment processing option.
Can i have customers buying using credit card without having to sign up for a paypal account? Meaning it would be standalone type

Secondly, i would also like to integrate affiliate features in my site.
Scripts that i found at the moment would be
iDevDirect, Affiliate Pro, Post Affiliate Pro
what would you recommend?

any other ideas would be much appreciated