'Real Housewives' Star Kim Zolciak's Mother Waging Legal War -- My Grandkids NEED ME!

In true "Real Housewives of Atlanta" fashion ... Kim Zolciak's getting dragged to court by her own mother -- who's DEMANDING the right to see her four grandchildren, TMZ has learned. Karen Zolciak filed a Petition For Visitation in GA Superior Court…