happiest or more happy?

We spent our most happiest days in the little cottage on the lake.(a?)
a. spent our happiest days
b. spent our more happiest days
c. spent our more happy days

“Shopping” Barbara explained “is a form of relaxation for me.” (b?)
a. “Shopping” Barbara explained, "is
b. “Shopping,” Barbara explained "is
c. “Shopping,” Barbara explained, "is

Correct answer:
a. spent our happiest days

I, too, have a doubt here…doubt about the placement of the comma:

c. “Shopping,” Barbara explained, "is

d. “Shopping”, Barbara explained, "is – I would like to get clarification on this

Which one is correct? Do we need comma outside the quotes or inside the quotes?

As Barbara explained, “Shopping” is a form of relaxation for her.

I think the answer for the first question goes to a. Neither more happy nor more happier is grammatically correct.

For the second quesiton, I think the answer should be c. ‘Barbara explained’ is inserted in the middle of a sentence. To show the continuation of the original sentence and the insertion of ‘Barbara explained’, I think commas are needed. Actually, I can’t explain it more… umm… just my gut says that. Let’s wait for wiser answers.