Yes, if your company has paid up support you really need to get on Wonderware's tech support site and look for some tech notes regarding upgrading from WW 7.x to 8.0
There are several issues regarding some of the addins that used to ship on the 7.0 cds that no longer come with 8.0
It is no big deal if you are familiar with WW, if you are not then you will be frustrated for a few days, but most of these isses are spelled out in tech notes on their eSupport site.
If you get stuck just send me an e-mail.
Oh yea, unless they make you do not upgrade the OS to XP.
Even though InTouch 8.0 is listed as designed for XP, most of the I/O drivers do not work quite right on XP. Unless the Siemens network you are using is supported by their new IO servers called DAServers. I would also update to that revision of IO servers at this time if they have the one you need released at this time.
Darren