Q1. Okay! So I have my session in PT 10 and I want to send it to my friend for mixing and I am not sure what DAW he uses! How do I export all my tracks to .wav in once? or is there any other way round to send my whole session?

Q2. I use Guitar Rig 5 for my guitar tracks and in my current session there are 13 guitar tracks. I want to save up on CPU power for mixing. How do I freeze (that's the term used in REAPER, don't know what's it's called in PT) my tracks?

 

I don't know about how to do all tracks at once, but you put a stem file/clip at the beginning of each track. That way, when you line up all the beginnings of the tracks in another DAW, you have a reference point and a way to make sure they are synced up.

 

With the edit window open (not the mix window)just highlight all tracks from the beginning to the end of the song and hit consolidate under the edit tab. All tracks will be made into equal length files which can be used in any DAW.

 

You could select the clips you want to export, then in the right pane, under clips, select "export clips as files'. But this method copies tracks without RTAS plugins. To use these, you'd have to bounce your project, track per track.

On a decent computer your track count (and dozens more) can be handled with a breeze. However, you could downmix and bounce your 13 guitar tracks to fewer tracks for a less cluttered view & workflow. It also would give other people that work on your project less headache..
When using many of the same plugins on your channels, you could use sends & aux tracks to put these plugins on (and use one instance of a plugin on an aux track, instead of a plugin per channel). That does free up more system resources then using fewer tracks.