So if I upgrade to PayPal Advanced for $5 I can begin to include "Pay with Credit Card" in addition to having "Pay with PayPal" button?
Correct, and the separate card checkout button will appear in your cart automatically when you enable PayPal Payments Advanced in your E-junkie Profile.
There is another button that comes with PayPal Advanced and that's "Pay Using PayPal Credit". Is there a way to remove that option from the cart?
PayPal requires us to show that option when the buyer's payment total is $99 or more, so there's no way to hide it; however, it doesn't affect you, as PayPal handles the financing at their end. Buyers who choose PayPal Credit would appear the same as regular PayPal checkouts from your perspective.