I will turn my word file to pdf and submit to createspace for publishing my book

Two questions:

1) should i just do a save as pdf or print pdf? which is better? my book has color images in it. which method preserves picture quality better?

2) when inserting pictures into my word file i made sure the picture files (all jpg) were at least 300 dpi (which is what createspace wants)... but now that these are inserted in my word file, that 300 dpi means distorted? or will it be distorted when i turn into pdf? if so what should i do?