yes it is. One of the best improvements in Vista is the new setup procedure which lets you load drivers off a flash drive or cd-r. XP is based on the same model that was used as far back as NT4, which is floppy or integrated on CD.
nLite is a great app. Slipstream service pack 2, and your cd key. Love it. A word of caution though, don't make too many tweaks, because sometimes it can really mess things up. Stick to basics.
BTW, you don't need to install SATA drivers when installing windows unless you have a SATA RAID array. A proper bios will "fake" a standard IDE controller to Windows setup, and after you get to the desktop you can load your SATA drivers the usual way. This may not be the case for RAID controllers that aren't a part of the northbridge - like say you have 4 SATA ports on the nForce4, and 2 more with a silicon image controller. The nForce ports will definitely work, but the silicon image ports probably won't.
I've been using SATA since the nForce 2 days and only had to load the drivers on setup once, and that was when I had a 2 drive RAID0 array. Make an nLite disk though anyway. Not having to type in your product key alone is worth it
Good luck
~MiSfit