Your favorite party music -- what tunes make you want to boogie?

I have a reason for asking -- we are beginning to build the song lists for FUNDAY RADIO, a twelve-hour program which provides the background sound for FUNDAY, the twelveth edition of which be held on June 17, 2006 here in Saginaw, Michigan (yes, you're invited).
Now, I have about 1400-1600 MP3s, most of which I conscientiously squirreled away back in the good ol' days before free NAPSTER got the ax. We've used this library to build our previous FUNDAY soundtracks, but I think we need some new stuff.
I have a pay program which will allow me to download darned near any song you can name, within reason. Obviously, I have very little newer stuff (within the last six or seven years) and I'm ignorant as to what the cool new music is (I don't listen to radio) or who to ask regarding that matter.
So please, kind DUers, help me out here. The party has guests between 16 and 60 and serves alcohol to those of legal age. Still, it's more a social gathering than a kegger, per se. The music includes rock, pop, some jazz in the evening and country-and-western sets scattered throughout. It would include some more hip hop, if I wasn't a total tard regarding that genre.
What music can you recommend for me to add to the FUNDAY library?
John
If I DO already have the song(s) you recommend/request, your suggestion(s) will still serve to guide me as to the stuff I should be playing. That, too, is a good thing and I'll surely appreciate it. Thanks for the help!

For recent hip hop I suggest N.E.R.D.

For general greatness and inducing booty shaking I recommend the song Slumber the Slum by the Five Royalles.

Have lots of other suggestions I could make if I wasn't distracted by my day job

I'll get to digging up those recommendations. Anything in particular I should start with from N.E.R.D.?
John
Now get back to work -- I don't want to get anyone fired on my account.

Mostly because I'd really like to hear what the DUers have to say re: party music and because I know most of the people who really need a party are probably at work (like tater) just now.
John
It is now, for those remotely interested, 188 days, 19 hours and 59 minutes to FUNDAY.