Putting in...

Pause 20

...will give you a 20mS delay... is there a problem simply using this in your code?

TMR0 is independant from the Watchdog Timer although they share usage of the prescaler (though not simultaneously). Turning WDT on or off has no effect on TMR0.

Since TMR0 is an 8-bit timer, that means you can only time 256uS (using a 4MHz clock) without using the prescaler. Obviouly adding in the prescaler will allow you to time further (depending on the prescaler setting chosen).

Melanie