The INF file should be OK with Windows 7, it just requires some shenanigans to download and install...
Well first, actually, you might not need the INF file. Plug in the LCD/backpack and see if it goes through the "installing driver..." process automatically (it does this on my Win7 box, but that might be an artifact of having previously installed the Arduino software/driver, which may be sufficiently similar).
If it doesn't
automatically install, try this:
First, on the LCD backpack tutorial page
, in the "Download" section at the bottom...right click
on the link for "INF driver file for Windows" and select "Save target as..." or "Download link as..." or whatever your browser of choice calls it (basically, some form of "save as" option). You'll be prompted for a destination (e.g. "Downloads" folder).
Plug the LCD/backpack into a USB port. You may be prompted at that point to locate a driver. If so, select the "Browse my computer..." option and select the folder where you previously downloaded the INF file (e.g. "Downloads"). It should locate and install at that point and be on its merry way.
If not, go to the Windows Menu and select "Devices and Printers." You'll see a generic icon in the "Unspecified" section. Right click on that, select "Properties," then the "Hardware" tab, then the "Properties" button, "Change Settings," the "Driver" tab, "Update driver...", and finally "Browse my computer for driver software" (who designs this stuff?) Select the folder containing the INF and it should proceed with the installation. After that, you should have a COM port (e.g. "COM10" or such) that you can connect to via terminal program at 9600 baud, or use the Arduino serial monitor.