When you use the upsize wizard you have to know the name of your server. After starting it, choose create new database, then type the name of your server (ServerName) then under user ID and password type the name and password with administrative privilages to write to the server. Usually the user ID = SA and the password= "nothing" unless your administrator has changed it. Give your new database a name and choose next. Then you can choose your tables to upsize. If you are still having problems check your Drivers. Goto Control Panel and choose ODBC Data Sources, choose System DSN and create a new connection to your server. There you can test the connection. You may need to install updated drivers on your system but I highly doubt you'll get that far with this problem.
If you don't remember installing SR-1 go to your control panel under Add/Remove programs and see if it is listed. Or you can choose About Access under the Help menu and see if there are any SR's installed. Check www.microsoft.com/office/downloads for the latest SR updates.