a couple of questions

I am taking charles laptop with me this summer while i am gone for 6 weeks.  i want to set it up so that i can get my email and sync my phone/ calendar/photos.
I would suggest using your parental control admin account.  That way you're not using his side at all. 

i think that i can set up an email account on his email program and just have a password so no one else on the computer can check them.  not sure????
Again, just use your admin account instead of using his email side.  Your admin account will have apple's mail program but clean.  His email will not appear.  The password will be for the entire user.  Not just email.  

is it possible to associate my iphone with the laptop just for the summer?  not sure how this would work - any conflict with mobile me?
You can do that but you'll have no music or video on the computer.  You wouldn't really need the computer.  Just fill your phone with music before you leave then buy any new music directly on the phone.  

once i get home in august, can i move all documents and photos from the laptop to my desktop?
yes, file sharing would do the trick.