Ubuntu newbie trouble installing wireless USB adapter

I have an older computer for my daughter that's struggling under Windows + Norton and hoping Linux will make it run better/faster.

Trying to boot with Ubuntu 10.0 CD to see how well it runs and how I like it.

The system connects to a wireless network via a Netgear N150 Wireless USB Adapter.

Ubuntu Wireless Troubleshooting says to locate the driver .inf, 2. install ndisgtk package, 3. open ndisgtk and select that driver. However, when i click the link to Install the ndisgtk package i get an error: Unable to load page, The requested URI "apt:ndisgtk" is invalid.

Saw on this forum to run terminal server and install via sudo dpkg -i /media/cdrom/pool/main/n/ndiswrapper/*.deb but it gives me an error too cannot access, no such file or directory, and when I look at the CD, i see why, there's nothing in the media folder and searching the cd for ndiswrapper, the only such file is under usr/src/linux-headers-2.6.35-22/ubuntu/ndiswrapper.

Any suggestions to get my wireless USB adapter installed, so then I can try to connect to the secure wireless network?

Also does running Ubuntu off CD-ROM do a good job mimicking what it'll be like if I actually install it, e.g. Firefox speed?