The simplistic answer would be, yes.
You say build a new system. My assumption would have been that you would reuse your existing case to install a new motherboard? I assume the Raptors are sata, so you would not run into the issue of new mobo's not having IDE ports on them for the hard drives, though if your cd/dvd drives are IDE, they will need to be replaced.
You should not have any issues getting the data off of the old drives, unless you run into permissions problems, which can be fixed. If you were using some sort of mail program, your old emails should be able to be imported back into the same program. Your Favorites/Bookmarks can be imported or copied depending on what you browse the internet with.
If your feeling adventurous you could try a couple of things to see if you can use your old load of Windows.
First, clone the drive with Windows on it to a new drive. Install the cloned drive into the new system. Boot the Windows install from the cd and do a repair install of Windows. Being that you were using an Nforce chipset, the best luck for this procedure would be to use an Nforce board again. Whatever the chipset, doing a repair install of Windows that was on one mobo, and now is on another, is a crapshoot as to whether it will boot Windows, but if you have the time, it may be worth a shot. Just do not use the original drive itself, use the clone, to safeguard your data.
Second is dependant on using similar chipsets. More so with VIA chipsets, I seen where just putting the old drive in the new system with the same chipset manufacturer, though the new board's chipset itself is newer, and the system ran through some driver detection stuff and it booted normally. I think I tried this on an Nforce and it worked as well. In trying this with Intel boards, the boards need to have the same chipset itself, like 440bx, 810, 845, 865, 915, 925, etc. Again, do this with a cloned drive to see if it works.
A new install of Windows is going to probably be the best way to go, as you are starting with a new registry, so you are not importing possible old issues, or having odd issues with old chipset residuals.
If you want to get data off now, these USB converters from Newegg work very well.
Good Luck
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