Windows 2000 on Compaq Presario says no audio devices are installed

I was given a very old Compaq Presario laptop and asked to make it usable. It had Windows XP and a lot of viruses; the audio was horrible, with too much noise in output.

I had a Windows 2000 Installation CD, hence decided to wipe out the hard disk and install Windows 2000. I planned to copy over lots of MP3 content and very old videos with VLC 1.1.11 installed. If the audio was still bad, I would attach some external speakers.

Installation of Windows 2000 went well, VLC 1.1.11 also got installed.
Now when I tried playing some MIDI content, VLC threw error about some Entry Point not found in kernel32.dll (I will try to fix this by trying out VLC 0.9.9, but this Post is not about that)
I tried Windows Media Player and it said “no audio devices are installed”

What could be the problem ?
How do I troubleshoot it ?
In case this is a software Issue, how do I get the appropriate Drivers for the sound card ?
In case this is a hardware Issue, Is there any way out ?