Have you installed SP2 or SP3 . SP2 dealt with the write errors. Go and uncheck enable write cache. Go to your disk drives in Device Manager and see if enable disk cache is checked. If it is uncheck it get SP3 apply it. Then you can go back and recheck it without worrying. Windows 2000 doesn't handle faster processors(900mghz) and fast Disk drives(7200rpm) to well. It shuts down too fast.
Here is an alternative but shutdown will take forever. http://support.microsoft.com/default.aspx?scid=KB%3bEN-US%3bQ146092&

This was the official line but like I said it has been fixed since then.
http://support.microsoft.com/default.aspx?scid=KB%3bEN-US%3bQ281672&

The other alternative is to make a recovery disk(erd) and run repair from the floppy. If the system crashes during shutdown you'll need it. Make sure and check back up the registry when you go to make the ERD. Make them often 2000 doesn't keep backups like 98. This will be the only way to get back in.