I didn't really have anything specific for the settings. I think the key was the treble control and the graphic EQ.
For the DT settings, I had the treble somewhere past 7. Again, it wasn't anything specific. Used my ears mostly. My mid knob doesn't do anything, so that's really not important what I had it at. Bass was really low, at around 2-3, pulled out. I always have the deep function pulled out too, as I'm using a 2x12 and want a little bit more low end. Volume (the one that sets the overall gain) and lead gain set to 7. Graphic EQ was based on Petrucci's settings. I may have added more or less mid range on the 750 slider. Presence knob was around 5. Whatever else I missed just mess around with until it sounds good to you.
The Metallica settings were basically an extreme version of the Petrucci set up. I tried using the Metallica setup with the graphic EQ (as seen from their old rig pictures), but that just didn't sound right to my ears. It was basically just an extreme V, where the bass and treble end were nearly all the way up, mid bass and mid treble were a bit lower and 750 was scooped all the way. I had the presence knob at 9. Gain stayed the same.