Mets closer Francisco Rodriguez picked an ob scure Bronx lawyer, Chris Booth, to defend the fiery fireballer against charges he assaulted his father-in-law last month — and it was a smart move, say local court-watch ers. Booth — who started as a busboy and then waiter at Mario’s, the iconic eatery on Arthur Avenue — is highly re garded by prosecutors and judges. Mario’s owner Joe Mig liucci, who’s married to Booth’s mother, Barbara, told us, “The kid is a real diplomat and a gentle man.”