Drivers

When I go into control panel and click on systems and then go to device managers I see the following under Network adapters

Dial up adapter
Existing Ndis 2 driver
Existing ODI driver
Yet there is yellow question marks beside the drivers ?

When I click on the existing Ndis driver it tells me this:
Device status
The Ndis device loader for this device could not load the device driver (code 2 )
To fix this click the update driver
When I do this it tells me I have the driver already installed.
I don't have the windows 98 disks.
How can i get rid of these yellow question marks and is this affecting the optum performance of my puter?

Also where can I find my sound card? I have had problems in the past and want to check what I got?

How does one do a good cleaning of your puter? Is defrag and system checker enough?
Thanks alot for your help
Julia