How's this?

void main (void)
{
unsigned long timer_tick;

while (1)
  {
/*-------------------------------------
Wait for P2.0 to go lo.
-------------------------------------*/
RESET_LOOP:
  while (P2.0)
    {
    P0.0 = 0;   // This was not specified.
    }

/*-------------------------------------
P2.0 is lo.  Set P0.0 hi.  Read clock.
-------------------------------------*/
  P0.0 = 1;
  timer_tick = read_100hz_clock ();

/*-------------------------------------
Wait for 5 minutes.  If P2.0 goes hi,
restart loop.
-------------------------------------*/
  while (calc_time_diff (timer_tick) < (5UL * 60UL * 100UL))
    {
    if (P2.0)
      goto RESET_LOOP;    
    }

/*-------------------------------------
Set P0.0 lo and P0.1 hi.  Read clock.
-------------------------------------*/
  P0.0 = 0;
  P0.1 = 1;
  timer_tick = read_100hz_clock ();

/*-------------------------------------
Wait for 4 seconds.  If P2.0 goes hi,
restart loop.
-------------------------------------*/
  while (calc_time_diff (timer_tick) < (4UL * 100UL))
    {
    if (P2.0)
      goto RESET_LOOP;    
    }

/*-------------------------------------
Set P0.1 lo and P0.0 hi.
-------------------------------------*/
  P0.1 = 0;
  P0.0 = 1;

/*** OK - Now What???  Exit??? ***/

  }
}

Of course, you'll have to write a timer-tick routine for the 100Hz clock and another routine to calculate the difference between the current timer tick and a previous timer tick.

Jon