MLG ABORTS TKOF AFTER WARNING HORN SOUNDS.

Narrative

AFTER NORMAL PUSHBACK AND ENG START WE MADE A SHORT TAXI TO RWY 1 AT MSY. WITHOUT EVER STOPPING WE WERE CLRED FOR TKOF. IMMEDIATELY AFTER ADVANCING THROTTLES; THE TKOF CONFIGN WARNING HORN SOUNDED. CAPT NOTED FLAPS IN UP POS (NOT SET FOR TKOF). CAPT REJECTED TKOF AND I PLACED THE FLAP LEVER IN THE PROPER POS FOR TKOF. WE NOTIFIED MSY TWR CTLR OF REJECTED TKOF AND EXITED RWY. WE TOLD HIM WE WOULD LIKE TO TAXI BACK FOR ANOTHER TKOF AND WERE CLRED TO DO SO. WE COMPLETED BEFORE TKOF CHKLIST AND WERE RECLRED FOR A NORMAL TKOF. MAX SPD DURING REJECTED TKOF WAS LESS THAN 30 KTS (ESTIMATED). CONTRIBUTING FACTORS TO OUR DISTR FROM COMPLETING THE CHKLIST WERE; JUST PRIOR TO PUSHBACK 2 OF OUR FLT ATTENDANTS ENTERED THE COCKPIT ARGUING WITH EACH OTHER ABOUT A PREVIOUS PROB WITH A THIRD FLT ATTENDANT. THIS DISTRACTED ME AS WELL AS THE CAPT AND WAS ON MY MIND AS WE PUSHED BACK AND TAXIED. ALSO DISTRACTING TO ME WAS ANOTHER ACFT TAXIING TO THE SAME RWY FROM THE OPPOSITE DIRECTION AND CALLING THE TWR FOR TKOF AT APPROX THE SAME TIME WE WERE ABOUT TO CALL. HE WAS CLRED FOR TKOF AND IMMEDIATELY WE WERE CLRED INTO POS AND THEN CLRED FOR TKOF WHILE WE WERE STILL MOVING.