DRG VFR FLT, N6586J ENCTRD WX, BGN CIRCLING HAY FLD FOR EMERG LNDG & MADE DISTRESS CALL ON EMERG FREQ 121.5 MHZ. N6586J WAS TOO LOW TO CTC ATC FACILITIES, BUT MONARCH FLT 58 (BOEING 757) HEARD THE PLT CALL & OFFERED TO HELP. ALBANY APCH CTLRESPONDED ON SAME FREQ (121.5) & FLT 58 RELAYED INFO TO & FM N6586J. ALBANY CTLR PROVIDED INFO OF 3700' MTN PEAK IN VCNTY, BUT PLT OF FLT 58 DIDN'T RELAY TRRN ELEV TO N6586J, NOR DID THE CTLR NOTE THE ERROR. BOSTON ARTCC ESTAB RADAR CTCWITH N6586J & BGN RELAYING VECTORS, BUT CTLR THOUGHT PLT WAS PROVIDING HIS OWN TRRN SEPN, BECAUSE HE WAS VFR. THUS, THE CTLR ISSUED VECTOR BELOW MIN VECTORING ALT (MVA), WHICH WAS 4000' OR ABV. PLT ENCTRD IMC & RPRTD DSCNDG TO 2500' TO "TRYTO GET OUT OF THE CLOUDS." SUBSEQUENTLY, ACFT CRASHED ON MT FITCH. ATC HANDBOOK ALLOWED VECTORING OF VFR ACFT BELOW MVAWITH NO WARNING OF TRRN. ATC CTLRS DID NOT ADHERE TO EMERG PROCEDURES IN HANDBOOK. THE INVOLVED SUPVRS TOOK NO ACTION TOCORRECT THE SITUATION. INVOLVED CTLRS LACKED TRNG IN HANDLING EMERGENCIES CONCERNING VFR PLTS THAT ENCTR WX BELOW MVA.