Paul,
The error that you get are probably because you need drivers for those devices.
The "mass storage controller" I have seen those on systems that have usb zip drives or Ultra ATA Hard Drives
The "Multimedia devise" This could be the Sound Card or in some instances some modems depends on weather or not they can support sound.
The "Serial Controller" It has to do with the serial ports.
You should be able to download the drivers from the different vendors support page.
The reason some of those things are working is because windows 98 is using the generic divers and the devices can use them for the most part.
good luck
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