JR pass validation

Hi

I'll be going on a 10-day trip, & will definitely be getting a 7-day pass. I will arrive in Tokyo on 5/11, & I intend to start using the pass only on 5/13. Can I validate the pass on 5/11, or should I wait till 5/13, & validate it just before I board the train ?

From what I found, the JR pass can only get me to Odawara & after that I will either have to buy tickets or get the Hakone pass, is that correct ? Is there any pass that includes the Hakone area as well ?

Thanks in advance