Light grooves are usually no big deal. Make sure the grooves are not manufatured-in to act as brake-surface wear indicators. If the grooves occurred while on your bike I would suggest checking and cleaning or replacing your brake pads to ensure debris is not causing further damage.

I would say that as long as the rim sidewalls feel pretty flat they are OK. When rims get worn out they generally have a concave profile that you can feel with your hand.