IMO, it would be better to keep the os on the smaller drive and use the larger drive for storage.
Is the vista 32 bit a full retail version? You can go to the harddrive manufacturers website and get a utility that will transfer your os to a new drive. In addition, install order should not make a difference. You can always use easybcd
http://neosmart.net/dl.php?id=1 to fix your bootmanager.
because of your first quesiton the following is something to consider.
if it is a system builders version and its already been used to install on another computer then you can never use it again, even if you removed it from the original comptuer.
In addtion you can never install a system builders version on a computer that already had an operating system installed on it.
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