Dell Inspiron 1501 - wifi

I have a Dell Inspiron 1501, using windows vista.  I am having problems using the Chicago Public Library wifi and was told to download the driver from Google. The problem is I found 4 different downloads and became confused as to which one to use specifically for my computer.  Does anyone have any suggestions please? 

Also if I might ask another question please: does either Dell or Windows Vista have a diagnostic tool which will scan my computer and tell me the updates I need? Thank you.