The computer will work perfectly fine without any .Net Framework.
But increasingly, applications and web sites are using .Net Framework, and so you may miss out if you don't have it installed.
The simplest .Net Framework application I can think of at the moment is Paint.net. You probably have Microsoft's default image editor called MSPaint in your Start menu > All programs > Accessories, but a project originally mentored by Microsoft but now developed separately is Paint.net and is an image utility with more features than the basic MSPaint.
Microsoft recently introduced Silverlight, a browser based component that was developed to rival Flash for animations, interactivity, and other web effects, and that is based on the .Net Framework.
Here's more on .Net Framework;
So, not entirely necessary, but you may begin to miss out on surfing experiences and some applications may require it.
I have a Dell Dimension 4500S, build number 2600, 256 MB, 2000 MHz, Microsoft Windows XP Home Edition.
I would like to know - do I need to have Microsoft .Net Framework loaded on my computer? If I don't need it, I would like to delete it.
Thanks for any advice out there.