Vidya,
I have a OLED 128x64 (OSRAM Pictiva) on my desk and it works fine (NOW)
regarding the row incrementing there is one setting which is critical for that:
OLED_WriteCmd(OLED_SETDISPLAYOFFSET); // 0xA2
OLED_WriteCmd(0x44);
the 0x44 depends on the specific display
Q-man