If anything does come out of this whole Geoff Tate gig, I really want Disturbed to cover Spreading the Disease from the Operation: Mindcrime album (since John knows all the songs on it now). I'm fairly certain everyone in Disturbed loves that album too.
Scott Rockenfield does this awesome drum intro that Mike could really bring his flavor to and have a lot of fun with, the main riff would sound amazing with Dan's tone, and that banshee-like chorus is so massive and powerful: it would be great with David's multilayered vocals.
Not to mention that low, slightly growly bridge Geoff does near the end that David could work wonders on (maybe he could update the lyrics to reflect the political turmoil of today). Plus, it has "spreading the disease" right in the title. It's a perfect cover for Disturbed.