OK, it's four hours flight but
Day 1:
Hop over to Delhi, get a taxi from the airport to Agra (about three hours on the new Noida Expressway) and if there's time when you get to Agra then have a wander around Agra Fort.
Day 2:
In the morning go and see the Taj Mahal.
Get there early and leave by mid-morning then get the car to take you to Neemrana Fort Palace Hotel (about 6 hours on fairly decent back roads through rural Rajasthan).
Day 3: Chill out at the hotel, taxi to Delhi airport takes about an hour and a half from there on the highway.
Delhi airport is decent and quick to get through. All in all the trip is a great little flavour of India with very little of the traditional Indian hassle.
In case you do go then its worth bearing in mind that the Taj Mahal is closed on Fridays. I did exactly the same trip about 6 or 7 weeks ago (and yes, I have been meaning to post a travel thread but, you know...). PM me if you want any info.