You don't need to a comma before the word "and". While a comma before "and" is acceptable, it isn't necessary unless the lack of a comma would lead to confusion.
ex. Some of the functions of Microsoft word include highlighting, copy and pasting, and underling. Since copy and pasting can be considered a single function (albeit I don't necessarily consider this to be true), inserting an "and" between them is necessary, and a comma after "pasting" is necessary to avoid confusion. In scenarios like these, it is necessary to insert a comma before "and", but in most other circumstances, it is largely based on personal preference.
All of your other commas I agree with.