why do the majority of the best roles go to jews?

Not really...I doubt that they're getting it just because of their religion. There's good Jewish and non Jewish actors who get roles.

You could say why are all British people getting the roles?

There are plenty of famous non-Jewish actors like Robert Mitchum,Tatum O'Neal,Lena Horne,Robert Redford,Jennifer Lopez and many others

I didn't know Tom Hanks was Jewish. He gets all the best roles.

I had noticed that there were alot of Jews in hollywood, but do not know if they made it through merit or connections.