Don't try to play anything that you haven't fully mastered if you want to impress. Make sure that you "own" the piece you want to play, and also be sure to add tons of feeling. That's what gifted/talented means to most people.

So, if you have to forgo Eruption and play the most soulful rendition of "Summertime" by Janis Joplin on an acoustic (alright, it's already pretty soulful, but you get my drift), playing only chords, do it. Play whatever it takes to be 100% confident that you'll blow them away.

Post an mp3 here before you audition, if you like. You'll be sure to get plenty of objective advice.