Jedi,
the only way is clone to the new server, boot from safe mood or from CD to replace all the hardware driver and later upgrade to win2000 then 2003.
However, u might want to evaluate the software compliancy between NT4 & 2003. Noted not all NT4 software functioning in 2003.
moreover, through my experience, upgrade from NT4 to 2000 will cause a lot of unexplainable system problem so expect the same when its go to win 2003.
the best thing is to dig back the Cd installation cd then just migrate over.
good luck!