Here's the exact instruction:

The UseHR Registry edit is supposed to solve one problem: fuzzy or jagged images in Internet Explorer when using a DPI other than the default 96 dpi, such as the 120 dpi that DELL has set on systems with high-resolution LCD displays which it has shipped (.e.g. WUXGA and WSXGA+).  If you do the Registry edit correctly, it will solve this problem.  There should be no problem with images in IE if you are using 96 dpi, and in this case, no Registry edit is needed; however, fonts will be rather small -- too small for some people.  So, if you want to use 120 dpi instead and have images appear correctly in IE, do the following Registry edit:

Go to Start > Run > type REGEDIT and click OK.  Once in the Registry Editor, click the + signs to navigate to the following key (folder):

HKEY_CURRENT_USER \ Software \ Microsoft \ Internet Explorer \ Main

Click on the "Main" key (folder) in the left pane to highlight it.  In the right pane, you'll see the contents.  Look near the bottom for a value named "UseHR".  If it doesn't exist, you'll have to create it.  To do this, right-click on a blank area of the right pane and choose New > DWORD Value.  Name it "UseHR" (without the quotes).  If you just created it, it will automatically have a value of 0 (zero), which is what you want.  If it already exists, and has a value of 1 (one), double-click it to edit it (or right-click > Modify), and change the value to 0 (zero).  Click OK and close the Registry Editor.

Open a new browser window and you should see the difference.  If not, reboot your computer and try it again.