Just try the conversion
You are on the right path. scsiport.sys should be updated to a later version. The "windows 2000 update rollup 1" came in a updated version, v2, later in 2005 at september 13th.
This later version of the scsiport.sys in this rollup carries a versionnumber of 5.00.2195.7059
Your steps 1. - 4. seem correct. I have just virtualized two servers today with Windows 2000 SP4. It didnt work first time, as I recieved 2 x BSOD. After digging with google and updating with the "new" rollup, booting and virtualizing both servers worked.
There can still be pitfalls as a third server doesnt allow me to install Converter 4.01 - alas, more time with google :-)