We did exactly that, jumped from Win98 to Vista SP1, the 64-bit "home premium" edition. New hardware, obviously, the old Win98 machine couldn't load & run Vista under any conditions.
We have had no problems with it other than the learning curve of figuring out how things are done differently between the two OS's.
We copied everything from the old hard drive to DVD & then created a "Win98 DVD folder" on the new hard drive & copied the DVD's down & have direct access to everything that was on the old machine.
Dumped McAfee (came with the machine) & have Norton 2007 running. Again, no problem with that combination.
Internet access is slow but then we're running 56kb dial-up so it's gonna be.
No huge fan of MicroSquish but, thus far, Vista has been OK.
