there are two ways to achieve what you want as far as permissions...
1.) when working as a non-priveleged user open a terminal and type su (this is the superuser command) it will ask you for your root password, enter it, you are now root in that terminal and can do what you need to.
2.)you can also do this--> as root... chown -R username:groupname /path/to/your/specified/webroot to the user and group that you would like to have doing the web administration this will allow that user to edit/save files to the directory and as long as its 755 apache should be able to still serve it up.
oh...and the windows partition dealie... try doing this
then change the permissions of the mountpoint while it is unmounted, after changing the permissions of the mount point mount the device again. Should work now.
NOTE:you will probably need to be root to edit the permissions.
glad you a least got the basics runnin, hopefully this will tie the rest together