How do I get my screen, graphic card, & Input Device settings to be detected correctly .

After downloading programs from the Ubuntu software center as I'm a first time user of Ubuntu it then went through the remove and install phase in which all of a sudden my screen went blank. After playing around with it I received the following message as an error occurred. It read "Your screen, graphic card, & input device settings could not be detected correctly. You will need to configure these yourself." I then click on OK and it gives me some choices in which the first is "run in low graphic mode" which it has for the last 12 hours and nothing changes and the other option that may work requires my desktop ID & password in which what I thought it was doesn't work leaving me with this problem. How do I configure? How do I get my screen, graphic card, & Input Device settings to be detected correctly? Thanks Mike