An MD11's SLAT DISAGREE level 2 message activated during approach. After a go around and completing the QRH procedure a normal flaps 15 approach and landing were completed.

Narrative

During our arrival we were vectored and slowed down by ATC to sequence us behind another aircraft. We were cleared for the ILS 30L and were on a 280 heading to join the localizer; level at 2;000 FT waiting to join the glide slope and holding 200 KTS. I asked for slats extend and the aircraft properly configured itself with slats. A short time later; out of the blue; the slats disagree level 2 message came on and the lower speed foot jumped up about 25 KTS activating the stick shaker for about 5-7 seconds. The Captain immediately extended the flaps to 15 to give us more lift and the lower foot; we discontinued the approach; and I added power and clicked off the autopilot. We asked ATC for a climb and a vector off the approach. We increased the speed to 210 and left the flaps 15 configuration until we ran the Slats Disagree Checklist. The checklist does not cover our situation which happened after the slats were properly extended. We elected to bring the flaps back up but not to retract the slats. We brought the flaps back out to 15 with no new warnings and continued to configure the aircraft for landing and had an uneventful second approach and landing. On the descent during the second approach; the slat disagree amber box in the lower left corner of the PFD flashed momentarily several times but never activated the level 2 message again. We believe we handled the situation correctly and to the best of our abilities; but are filing this report because of the stall warning activation.