Sub Digital Pins 0 and 1 (RX, TX)

Hellow sir, Can you please tell me whether I can use Digital Pins 0 and 1 (RX, TX) for Digital I/o pins.

what are the conditions for this Please reply at the earliest . Thanks in advance Subramanya

Yes, those are normal Digital IO pins. The only caveat is that the Serial interface uses them, so if you use them for something else then you cannot use Serial and you may not be able to load new code onto the board with things connected there.