"I've never had to install Win7 before but I'm going to be setting up a dual boot with Win7 and linux. I need recommendation. Yes. I know. I shouldn't install Win7 at all."
if you need it use it, it is your right to use the tool that can help you complete the task you need to do
about space, how big is the hard disk?
is a desktop pc or a laptop?http://www.pclinuxos.com/forum/index.php/topic,69910.0.html
apart from that link i can tell that a big swap is a waste of space if you have more than 2 gb of ram and ralely use big apps like edit images or lots of virtual machines, my netbook with 1 gb of ram ralely uses more than 500 mbs of ram from 1gb available and no swap at all, that is using lots of apps and kde4 with compiz and also some windows app on wine
about a shared partition linux can access perfectly without a single problem all the folders of that win 7 install, windows is not as smart as this so if you want to share files with windows from linux you will have to copy from linux to windows or create a ntfs partition to leave files for both os but if you don't need to do this forget this extra partition
about installing windows and linux, if i remember correctly grub can handle both os, first install linux, then windows and after windows finishes to remove mbr restore it with the livecd you used to install linux, fixmbr should do it, if this is not enough i remember a article on the pclinux magazine talking about this more extensively but maybe it is a old article
the size of each partition depends on the size of the hard disk and the usage of each os, win 7 will need at least 50 gbs of space, the thing wastes around 30 gbs in god knows what including a ghost partition with 100 gbs but in reality is only 16 or 14(can't remember now)
for linux if you are going to have a /data or /home partition your / partition can be small(10 to 15gbs) but if you are only going to have / partition and swap your / should be around 40+ because all the home folder files will be stored in /home/thenameofyouruser and that is ok, i have done it since 2007 in pclinux and forever in all other linux distros i have installed and used
the rest could be a shared partition for both os or just split the hard disk and half for linux and the other for windows