
Plug the stereo audio outs from the MPC into the MBox Mini DI inputs.
Record the output from the MPC to a stereo track in Pro Tools.
If you want to split up the MPC sequence/song onto multiple tracks in Pro Tools, then you need to work out how you are going to do that.
If not already doing so, you might want to organise different sounds onto different MPC tracks, so you can solo and record one MPC track into Pro Tools at a time, depending on how you want the sounds split up inside Pro Tools.
Then, if recording more than a stereo pair into Pro Tools, you would need to sort out sync between recording of different tracks, so they are in time with each other once inside Pro Tools after being recorded in separate takes.
You options for sync are to use a MIDI interface on the computer, for the MPC to sync to Pro Tools over MIDI, with MIDI Time Code or MIDI Beat Clock as the sync protocol...
or
...you can use some sort of audio sync pulse/click/etc. signal, that is the same on each track/recording pass, and that you zoom in to sample level after recording and line up the different recording passes/tracks visually using the sync pulse/click/etc.
You could, for example, set the metronome to count in on playback at the start of each track/recording pass, and visually line up the metronome clicks.