Not to change the subject, but just making sure you know that using a credit card at an ATM will cost you a hefty finance charge as a "cash advance" from the credit card issuer. Using a debit card at an ATM may incur a small fee from your bank, the ATM bank, or both, but nothing comparable. Bring your bank debit card to get cash from ATMs, your credit card for major purchases if you want. For both, call the issuer before you leave to let them know your plans so they don't cancel when they see a foreign transaction.
In my experience swipe credit cards are generally accepted unless perhaps you're in a small town or business off the beaten path. As others have said, the automated ticket, toll, and gas pump machines may not accept them, but you can always pay a person. (They're not going to give away their gas, are they?)
Not to change the subject again, but the sooner our banks and merchants "evolve" to chip-and-PIN the fewer Target-type mass ripoff scandals we'll see. Hopefully we will evolve to Europe's level of civilization on this score (if not on others). ; )