A cry for musical help

I feel like I have most parts of this wedding under control, with one glaring exception - the music.  We booked our DJ eons ago and then I promptly put "deal with wedding music" in the furthest recesses of my brain.  Now that I can count the number of weeks until the big day on one hand, I figure I should probably resurrect my focus on the wedding music. 

Don't get me wrong - I am a relatively big music fan, and I really enjoy a well-constructed playlist.  However, my music fandom is pretty passive.  If whatever's playing on the radio is decent, I'll keep it on.  If it's stinky, I'll change stations.  Rarely am I so impressed by an artist, album, or song to go out of my way to make an iTunes purchase.  My personal music library is mostly comprised of musical and movie soundtracks and Top 40, so I don't necessarily think that's the ideal soundtrack to a wedding reception.  As a result, my library of "songs to be played at the wedding" is pretty tiny, mostly because I've never taken the time to compile a list of any form.  Unfortunately, my inactivity over the past months has segued into sheer anxiety; I feel like a reception's music can make or break the evening, and I definitely feel like the pressure's on to pick some sweet booty-shaking tunes.  I want the dance floor to be active, but I don't feel like I'm necessarily up to the task to get people out there in the first place. 

So, to sum up, this is what I don't want:

Image via Where's Matthew?

And this is what I do want:

Image via and Photo by Luster Studios

I figured that I would confront my own musical shortcomings by turning this task over to the online community, which leads me to my most pressing of questions: What song would get you on the dance floor at a wedding reception?  Fast or slow, new or old... I just want to hear any and all suggestions you've got up your sleeves!