Lisa mostly just wanted to get the introduction thing over with and volunteered to say something early enough in the class. After stating her name, though, she blanked for a second because how do you quantify everything you've learned growing up and spending half your time with Muggles into 3-5 things?
Eventually, she said that Muggles use electricity instead of magic, that they use mechanical vehicles instead of brooms or carpets or the Floo or apparating, and that with the technological advances of the last 200-300 years (especially the rapid advances that have taken place in just the last half century) Muggles in developed nations have largely abandoned the superstitions and religious beliefs that once caused them to lash out violently against witches and wizards.