Currently I have a ThinkPad x60 which .Net Framework 1.1 and 2.0 comes pre-installed. I have been tying to install the Service Pack 1 but to no avail. From the event viewer, I can see some errors being logged.

If I were to installed Visual C# 2005, can I get the application to point to 3.5 instead?

Also I read that to implement 3.5 I need to make sure that the previous versions need to be installed. If I dont install the service packs of 2.0, what is the impact?