We've stayed at the Luxor, MGM Grand, Golden Nugget (downtown) and Stardust (R.I.P.) and never had a problem with noise late at night. Some hotel reviews will mention rooms that are more noisy (e.g., Treasure Island facing the boats, downtown hotels facing the Fremont Experience). I'm not real clear as to why you're going to Vegas at all, esepcially in mid-summer. It doesn't seem that your wife and father are that enthusiastic. And in the July heat, it's not the healthiest environment (though many people just stay inside all day). In July I'd much rather be at South Lake Tahoe, with cooler temps, better scenery and lots of outdoor non-gambling activities.