B737-300 CREW HAD FO AIRSPD FAILURE AND A FALSE STICK SHAKER DEPARTING BWI.

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ACFT ARRIVED BWI WITH #1 IRS FAULT. 20-30 MIN MAINT DELAY TO FIX PROB; ADVISED PAX. ADVERSE WX (WINDSHEAR) DEP RWY 28 (ATIS ADVISED WINDSHEAR; 2 B757 ACFT PRIOR RPTED PLUS 15 KTS ON DEP).FO ROTATED AT 161 KTS (V2+20 V2-141 KTS). IMMEDIATELY AFTER ROTATION; STICK SHAKER ACTIVATION; NOTICED FO AIRSPD HEADED FOR ZERO. CAPT TOOK CTL OF ACFT AND CONTINUED ADVERSE TKOF PROFILE. AS WE BEGAN TO ANALYZE THE PROB AND LOOK FOR CIRCUIT BREAKERS; WE NOTICED NO CIRCUIT BREAKERS POPPED; BUT NUMEROUS AIR DATA COMPUTER PROBS; ALONG WITH NO ALT; TIME; OR DISTANCE INFO ON THE IRS FMC. ALSO; NO AUTOPLT FUNCTIONS; EXCEPT FOR CTL WHEEL STEERING. DECIDED APPROPRIATE ACTION WAS AN AIR RETURN TO BWI; AS FO AIRSPD WAS GOING FROM STICK SHAKER TO CLACKER SPD AND BACK. QRH REFS GND SPD; WHICH WERE ALSO UNAVAILABLE. ADVISED ATC OF AIR DATA AND AIRSPD PROBS AND REQUESTED A RETURN TO BWI. ADVISED CABIN CREW; PAX; MAINT; DISPATCH; AND OPS. CHANGED ACFT AND CONTINUED ON. SUPPLEMENTAL INFO FROM ACN 571927: LOSS OF #1 AIR DATA COMPUTER RESULTING IN UNRELIABLE A/S. INBOUND CREW HAD #1 IRS FAULT LIGHT DURING LNDG. MAINT REPLACED #1 IRU AND DID AN ALIGNMENT; WHICH FIXED THE PROB. PREFLT AND TAXI WERE NORMAL. WE DID AN ADVERSE PROCS TKOF WITH INCREASED ROTATION OF 161 (V2+20). TKOF ROLL NORMAL UNTIL JUST AFTER ROTATION WHEN I GOT THE STICK SHAKER AND NOTICED MY AIRSPD INDICATOR DECREASING THROUGH 90 KIAS. I GAVE THE PLANE TO THE CAPT; WHOSE AIRSPD WAS WORKING. COMPLETION OF THE 'AIRSPD UNRELIABLE' QRH REVEALED THE FOLLOWING FUNCTIONS OF THE FMC WERE INOP: GNDSPD; TIME; DISTANCE; AND FUEL REMAINING ON THE LEGS AND PROGRESS PAGES. THERE WERE NO POPPED CIRCUIT BREAKERS. WHILE THE CAPT WAS FLYING; HE NOTICED THE AUTOPLT WAS ONLY WORKING IN CTL WHEEL STEERING MODE; AT THIS POINT; WE DECIDED TO RETURN TO BWI. TALKING WITH MAINT CTL ON THE NEXT DAY; WE FOUND OUT THEY REPLACED THE #1 AIR DATA COMPUTER.