BleepingComputer.com: Most hardware doesn't work

A laptop I got from my brother earlier this year was riddled with viruses that were ridiculous to the point that they somehow I couldn't open any antivirus software OR do any google searches/pull up websites for antivirus-related help (all other sites worked), so I took the Windows XP operating system CD, erased everything on the computer and started from scratch. I just got the OS installed yesterday.

Now, I figured this would be the perfect solution but now much of my internal hardware doesn't work right because I don't have the correct software for it. The two I noticed were the sound, wireless internet and, as I tried to play a computer game I had just installed, some DirectX 3D thing. I found the list of other things it showed were present but not installed but I don't have it next to me because I'm on the internet with a different computer. I can get it if necessary.

Can I possibly download the required software for those things on this computer and burn the files on a disk/transfer it some other way onto the other laptop? Or better, how can I get the other laptop to recognize the wireless network and hook up to it so I can get everything I need?

You need to go to the manufacturers web site & download the drivers for it.
If there is a chipset driver install it first.

You will then need to go to Windows update & get all of the updates for XP.