Ok. The instructions from the
Installation Wiki are straightforward as long as you read through and take your time.
First of all, you need the kernel sources installed. Since you are using Ubuntu (which is Debian based), you may be able to install Ndiswrapper via Synaptic. Open up Synaptic and look through to see if it's there.
http://ndiswrapper.sourceforge.net/ details how to add the link to the ndiswrapper download.
If you need to install via a tar ball, you will need to have your kernel sources installed - check Synaptic for the package. Most of the install is done via the command line, so you will need to have a terminal open to do this.
Some of the commands need you to be root - you usually do this by typing
Code:
su
<enter root's password
Since you are an Ubuntu user, you would simply type
Code:
sudo <command>
<enter your password>
Work through the installation instructions and post back if you get stuck.