M Powered 8 Questions

[protools123]

I am going to be doing some recording for a band soon, and have some quick questions. First of all, how many tracks can I have of audio all together, not MIDI, but just plain recorded audio. This is the first time I will be pushing Pro Tools past 8 tracks, and will be doing guitar overdubs and things of that nature on top of a 6-8 track piece.

I currently have a Profire 2626, and am wondering what would be the best way to expand to 24 track capabilites. We are looking at getting a Yamaha M7 48 channel mixer, and I guess that is a 2nd part of my question. I will have 8 of the Aux outs as monitor mixes on stage and then the other 8 outs for PT. I hear there are expansion cards for the M7, will they give me more outs into whatever interface I will get. What interface should I get? Is this "Lightpipe" thing sending the audio as seperate tracks into PT, or as one group out, and as one track? If I used the MY16-AT 16 channel card, and connect it to my ProFire 2626, would I be able to use the 8 Inputs from the 2626, and then get an additional 16 by using the card? I am not sure if I read this right or not, but say I'm doing a live recording or something and I want 24 audio tracks, lets say mics, at once it is impossible. Woult PT9 be able to handle this.

Thanks in advance. I'm running the latest version of M Powered 8 on XP SP3. I could update to win 7 if possible.