NET Framework 1.1 is quite old and any number of later release should serve your purposes.
I suggest downloading/installing NET Framework 3.5, SP1, available at http://www.microsoft.com/downloads/en/details.aspx?FamilyID=ab99342f-5d1a-413d-8319-81da479ab0d7
. Once downloaded to your desktop, just install.
3.5, SP1 includes elements of 2.0, 3.0, and 3.5.
I used to have ATI cards so I know how irritating driver installs can be