New owner needs some advice please.

[Keepingtime]

Greetings, I have recently acquired my father's old DateJust Rolex. He has had it for years and it is well worn, but still had the original box with it. My questions are as follows, and please forgive me if the answers are given elsewhere in the forum and I have over looked them.
The first is what would be a good way to clean the watch and give the scratches out of the lens? It is not as bad as the picture shows.
The second is I plan on never getting rid of the watch but am not pleased with the dial color. I would like a black dial. Is that at all possible and at the same time should I have it serviced? My dad had it done about five years ago and it keeps great time. Thank you all once again in advance.