There's a free shuttle (Music City Circuit) that runs frequently (Downtown & Gulch lines) through downtown Nashville. Hampton Inn & Suites is near 4th & Broadway and Holiday Inn Express is on the corner of 10th & Broadway. If you look at the map, Hampton Inn is close to to both the Green and Blue Circuit and not too far at all from the Purple Circuit. Holiday Inn Express is close to the Green Circuit. Are you looking to go anywhere in particular?
Here's a map: http://www.nashvillemta.org/PDF/2010...ASystemMap.pdf
As for noise at the Holiday Inn Express - I would suggest you request a room that faces opposite of Broadway (toward Commerce Street).