for the 80's track:
Stevie Nicks - Stand Back

and the other 2 tracks are:
Madonna - Don't Tell Me
Jackson 5 - I Want You Back

Thank you, but the last one isn't Jackson 5

Still hoping for an ID

I'm positive that it is. The Jackson 5 track was released in 1969 and the track those rappers sampled from sounds exactly like it. If you listen carefully the beat is looped and repeats the same strings/violin part over and over. Here's a sample of the original track: link

Ah, I hear it now.

The Soulwax sample sounded completely different though. I think the sample used by them was the Jay Z remake?

Anyways, thank you!