My advice is to beak doen the mountain of problems into smaller chunks and deal with them individually. I realize this is easier said than done....

For instance:
The PEG tube is the least of your worries. This is really not a big deal to install. It takes only 20 minutes or so, you are in and out of the hospital in a few hours. Although, it may take a little while to get used to it (mentally). Initially, the idea of having that thing bugged me too. However, that wears off quickly. Now I hardly notice it is there. So far I did not have to use it, I am on radiation #14 of 33 and am still able to eat normally. However!!, the problem is that for a few days now everything tastes like cardboard i.e. rather disgusting, which means it is a chore to eat even tough it is not painful yet. Consider also that later on during radiation it will be painful or very difficult/impossible to eat. It also makes perfect sense to install the PEG tube early on.
In addition, the PEG tube also allows you stay hydrated which is important throughout the treatments. The PEG tube IS your friend! This is my personal view, but please check out the discussions in the forums here and also do a search on the OCF web for PEG amongst others you will find: www.oralcancerfoundation.org/dental/tube_feeding.htm

With respect to the teeth. Perhaps others can weigh in more here. This seems to vary between people, some keep them while others do not. In my case this has never been an issue and I still have most of mine (one tooth was removed as a favor when I had tongue surgery by a very kind surgeon). I am GUESSING that this may have to do with dental health, the irradiation volume/site and possible interference with the radiation. Had it been necessary to remove them (the teeth) I would have done that too, considering what is at stake.

Chemo: sometimes this is done before radiation as an induction therapy to shrink tumors prior to surgery or radiation, sometimes it is done together with radiation and sometimes it follows or is continued after radiation. You need to discuss with your MO which is going to be used and why.

Best of luck!