You will want an overall assortment of denominations. Smaller bills for tips, etc. and I have never had a problem using larger bills in restaurants. Once in a while you will see a sign indicating they do not accept UD $50 or $100 but that is usually smaller places.

When on the French side you will likely get your best exchange rate (or 1:1) when using cash and I doubt denomination will be a problem..

Not sure if I am reading your post right about the credit card and fee. If you want to consider a card without the foreign fee, Discover does not charge the fee and neither does Capital One.