Pilgrimage with my dad to Shea and Yankee Stadium in June 29th & 30th - Yankees at Mets and Rangers at Yankees....

Subway series is sold out, so I'm looking at ticket brokers.

Never been there.  Tickets are expensive, so I don't want to get seats that stink.  Any advice on best seats or better yet, what to avoid?  ie:  obstructed views, etc.

Also, is the Yankee Stadium tour worth it?

I would appreciate any input you may have

Thanks!