First of all, don't at all use dull backgrounds
Do Use indivisual pictures as backgrounds.
Next, it need not be much attractive.
Further more, don't forget slide transitions and SOUND.
Other common criteria like animations ought to be filled.
Well, make sure you have at least Ms powerpoint 2007.
However, 2010 edition is much much better, specially in the case of Powerpoint.
Best of Luck.