windows identifies it and goes looking for a pre installed driver to suit it. XP and Vista only carried a small selection of pre installed printer drivers so for the most part this search ended in failure and if you then ran the CD to provide the driver it confused windows so much that it led to complications. For this reason printer manufacturers recommended running the cd before connecting the device so that when you did connect, windows would have a driver in it's data base to use.
Windows 7 comes with a massive amount of printer drivers, just about every printer that has been tested and passed as compatable will have it's driver pre installed so by not running the CD all that is lost is the free software that is bundled with the printer and you can install that as an after thought.
Win 7 also has another feature that is very useful if you dont have the CD for a particular printer, just plug it in, win7 will look for a driver and if it can't find one pre installed it will go to windows update web site and check for a suitable driver there, if it finds one it will download and instal.
I doubt that the other problems you are having are connected with this printer event unless having discovered that the system was reacting to the printer being plugged in, you aborted the process and left the printer half installed. My advice would be to unplug the printer, go to printers in control panel, and if the printer exists, delete it and start again.
HTH
I resently purchased a HP Deskjet D1660 printer for my daughter and before reading the instructions she plugged in the usb cord into the computer. The instructions clearly state DO NOT PLUG IN USB before installing the software. Somehow it installed into the memory of her operating system. I manually removed the printer but we are now having problems with the RAM and programs are not working properly. Previous to this problem I had just installed a new 500gb harddrive and Windows 7 Premium. I have tried system restore and checked the memory but to no avail. I would really appreciate ANY help!

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