This piece is a really delightful piece by Mozart and is part of his Piano Sonata No. 11 in A major, K. 331. This theme is really unique in style and mimics the style of Turkish Jannisary military music. The track was also used as the soundtrack for "My Life as Mcdull" but Cantonese lyrics were included for the movie. This track is another manifestation of that pure musical genius that many believe found its supreme embodiment in Woifgang Amadeus Mozart.
Mozart - Turkish March (mp3)
Credits to Malek for providing the download for the track above.
And here's the piano score to Mozart's Turkish March by free-scores.com
Turkish March Piano Score [Download PDF]