B737 CREW HAD FLAPS FAIL TO EXTEND AFTER DEP FROM BLOCKS.

Narrative

DURING SINGLE ENG TAXI; #1 ENG RUNNING; FLAPS DID NOT EXTEND WHEN FLAP HANDLE MOVED TO FLAP 1 DEG POS. WHEN FO STATED 'FLAPS DID NOT EXTEND;' I DECIDED TO CONTINUE TAXI BECAUSE I WASN'T SURE IF THIS WAS A NORMAL INDICATION DURING SINGLE-ENG TAXI AND/OR I KNEW I COULD FIGURE OUT THE PROB ONCE I GOT CLR OF THE RAMP AREA. I AM UNFAMILIAR WITH SINGLE-ENG TAXI COCKPIT INDICATIONS BECAUSE I NEVER DO SINGLE-ENG TAXI UNLESS REQUIRED BY MEL. IN THIS CASE; APU WAS INOP/MEL'ED AND I HAD TO WAIT TO START #2 ENG ON TXWY. AFTER STARTING THE #2 ENG FLAPS EXTENDED BECAUSE 'B' SYS WAS PRESSURIZED. WHEN FO PRESSED THE RECALL ANNUNCIATOR; THE HYD ANNUNCIATOR STAYED ILLUMINATED AND I LOOKED UP TO SEE THAT 'B' SYS ELECTRIC HYD PUMP LOW PRESSURE LIGHT WAS ON. I COULD NOT FIND POPPED CIRCUIT BREAKER FOR 'B' SYS ELECTRIC HYD PUMP SO I RETURNED TO GATE. ONCE IN GATE; I LOCATED CIRCUIT BREAKER; RESET; AND PUMP WORKED NORMALLY. AFTER CONFERRING WITH MAINT CTL AND DISPATCH; THE FLT DEPARTED WITHOUT INCIDENT. CONTRIBUTING FACTORS: I HAD BEEN ON 4 WKS VACATION. DURING BEFORE START CHK; I FAILED TO SEE 'B' SYS ELECTRIC HYD PRESSURE LOW. DURING AFTER START CHK; I ALSO MISSED INDICATION. UNFAMILIAR WITH SINGLE-ENG TAXI COCKPIT INDICATIONS. PREOCCUPIED WITH MAKING L TURN IN TIGHT RAMP AREA WITH ONLY #1 ENG RUNNING.