Some interesting points are well noted by rohan,amdo,raindeer.
I have a different view of it, I believe shahjahan is great in his love but Tajmahal is neither love palace nor a mausoleum.
In 1983, the Taj Mahal became a UNESCO World Heritage Site.
Contrary to what visitors are made to believe the Tajmahal is not a Islamic mausoleum but an ancient Shiva Temple known as Tejo Mahalaya which the 5th generation moghul emperor Shahjahan commandeered from the then Maharaja of Jaipur. The Tajmahal, should therefore, be viewed as a temple palace and not as a tomb.
Taj Mahal alias Tejo Mahalaya, is an ancient Hindu temple complex in Agra. For the last 300 years the world has been fooled to believe that this stupendous edifice was built by the 5th generation Mogul emperor Shahjahan to commemorate one of his dead wives--Mumtaz.
From the well inside the Tajmahal, each and every view such as the frontal view and dome with the lotus flower cap, Hindu horizontal crescent and the coconut top at the pinnacle,the red lotus at the apex of the entrance, Vedic style corridors clearly suggest that so called Tajmahal is an altered version for Tejo Mahalaya.
Shahjahan might have been a true lover but Tajmahal is never his construction, he unfairly modified the place of divine and portrayed it as his own love palace fooling all the world leaving a mark of disgrace to the society. He was also so stingy as not to want to spend much even on converting a robbed Hindu temple into an Islamic mausoleum. Historic evidences make us understand that Tajmahal is originally a temple built long time ago by Tejaji.Some of the evidences:
* Carbon dating of samples taken from the doorway of the Taj Mahal from the side of the Jamuna rivers revealed that the door was 300 years older than the period of Shah Jahan. The carbon dating was arranged by Marvin Miller, an economist in New York.
* Johan Albert Mandelso, a European traveller who visited Agra in 1638, seven years after the death of Mumtaz Mahal, vividly described the life of the city in his memoirs, but makes no reference to Taj Mahal or any large construction activity going on to build it.
* Peter Mundy, an Englishman, visited Agra within a year of Mumtaz’s death. From his writings, it appears that the Taj Mahal was already a noteworthy building well before Shah Jahan came to power.
I hope this information helps you in the preparation of your speech enna, I wish you the best.