Grinding is not good. Check your pads and replace immediately if they're thin. It sounds like the rivets are digging into your rotor(s). Some places that sell brake pads will "turn" your rotors for free, which will eliminate the grooves. The rotors have a minimum thickness, and the shop will mic them to see if they can be "turned." If they're out of spec you should replace the rotors.
The other thing to check is your wheel bearings, inside that little cap on your rotors. You may need to check those and repack them with grease, or replace them if necessary. It's easy to do.
Those are the two things I can think of for your situation. Let us know if you need any more help. [img]smile.gif[/img]