This is a semi Mathematical question... In 2 parts
1) How many years before the same Phase of the Moon occurs on the same day Example if it was "Full" on Jan 1st this year,How many years pass until the next full Moon on Jan 1st?
And 2)
And say it was "Full" on February 29th 2002?( last Leap Year)How many years must pass before the next "Full" Moon on a Feb 29th?(and could the "time period" be variable?)

The 365.25 day tropical year cycle and the lunar cycle of approximately 29.5 days coincide with a period of approximately 19 years. So whatever phase of the moon occurs on January 1, in a certain year, the same phase will occur on that same day 19 years later.

This is accurate, however, only to within a few hours, so after some 150 years, it drifts off by a day.

As for the leap-day part of your question: I think the right answer is the leap-year cycle of 4, multiplied by the 19-year cycle above, meaning a repetition only every 76 years. I'm not entirely sure of this, and it also fails to take into account what may happen when the 76-year period spans one of those years in which a leap year is skipped (every century unless divisible by 4.)

also

This period is called the Saros cycle. Thought to have been known by the time of the Chaldeans, perhaps 1,000 years nefore the zenith of Egyptian astrology.

Because it relates to lunations it also predicts of eclipses. About 18.3 years