Motherboard Swap On Dual-boot Windows 7 / XP System?

I want to keep XP for compatibility reasons with some older hardware I still use often. I have XP installed on one hard drive and Windows 7 installed on another. When I installed Windows 7, I just went with the option for it to install a boot manager, and have been using that one ever since to dual boot my system. Nothing special, but it works.The current motherboard is an ASUS model, and has always had problems with the USB section (it took me quite a while to realize it was a motherboard problem, though). Then it began to develop problems reading the DVD drive several months after I installed it (back when it was only an XP system). Once again, not suspecting the motherboard, I replaced the DVD drive, thinking it had gone bad -- it hadn't, works fine in another system. And pretty soon thereafter the current drive began to work sporadically, and now doesn't work at all. Same as before.

This ASUS mb has a 3-year warranty, and it's not quite 2 years old. So, I should probably just suck it up and jump through the dozen or so hoops they toss in your path to get the mb repaired/replaced. Still, I'm guessing that if I'm successful, I may end up with a mb that is different enough from the one I have now where it's gonna break Windows 7 and XP.

I went through this when I originally replaced the motherboard, and ended up having to completely reinstall XP, reactivate it, and then d/l all the updates. I guess I'll be looking at having to do this now for both OSes, eh? If I have to reinstall both OSes, I'm thinking that I should install XP first, then Windows 7, mostly to preserve the dual-boot capabilty?

If I don't get satisfaction from ASUS, I'll probably just drop back 10 and punt, and go with a new mb. I'm gonna try to avoid this though because it's getting harder and harder to find mbs with PCI slots (I need three). I guess if I do this, it will probably amount to the same amount of work as if ASUS sends me a board that is substantially different from the old one.