I volunteered for a year at a nice one in the countryside which was nice (I went part-time at my old job so spend one day a week at the school and would take a weeks leave the go up the school for the whole week), although you get different problems such as parents riffling through the teachers desk to find out if there kid is top of the class, etc etc.
In my area of the country the majority of the schools are bad.
So I had volunteered for a year and abit, and did 6 months of the PGCE, specialising in childrens entertainer years 1-4. I was even told by the teacher not to attempt to teach them to right during my assessment as they would be uncontrollable
I tried it once and one little boy went insane half way through the lesson, strangled a girl, kicked the TA, throw chairs around, I had to raise the alarm for the behaviour manager to come and restrain him why I evacuated the class room with all the other children.
At this point I realised what a massive mistake I had made, triple the hours, 33% less pay and the hell of the classroom.
Have you volunteered at a few schools? By your questions it seems like you haven't, I would go ring up your local school and see if you can spend a few days there before you start PGCE... I guess it's too late now.
EDIT: you don't get a choice of placement and you won't get a choice in your first teaching job. Be prepared for an organised Zoo setting, then if you get a good one for your training then jackpot! Just realise 95% of the schools are crap wholes, if you can get a thick skin and accept that bad behaviour will be rewarded with toys and swimming trips then teaching is for you!