Tweak UI is a utility program written by Microsoft that brings together many system settings in one place.
It appears in the control panel.

It is one of the power toys from microsoft.

Tweak UI is on the original windows 98 CD:
substitute the drive letter of your CD ROM drive for the D.
Go to step 4 for instructions on how to install it.

As of 3/30/1999 it was also available at

Known problems with Tweak UI.
 1-There are two check boxes that control the clearing of the run, typed Internet Explorer URL's, and recent documents.  A single check box controlling these on the IE4 tab and three separate check boxes on the paranoia tab.  I would suggest clearing the check box on the IE4 tab and using the ones on the paranoia tab.
 2-There are two check boxes controlling the display of the Internet icon on the desktop.  One on the IE4 tab and two on the desktop tab.
 3-The automatic log on feature on its network tab does not always supply the password.  I have received a report that this behavior may be caused by having printer sharing active on your computer.
 4-The wrong help text is displayed when you right click on entries on the IE4 tab and select what is this from the pop-up menu.
 5-The create as a file feature on the desktop tab does not work.
 6-The installation path option is not available on the Tweak UI general tab in the special folders section if the existing path is not valid or available at the time Tweak UI is launched.  You can repair that by editing the registry key
You would need to change the value SourcePath in the right hand panel.
You can also download and double click on it.
This reg file sets the install path to C:\ which should exist on any system.
You can then launch Tweak UI and point the path to the correct location.

Installation instructions
1-create a file named power in the root directory of your drive.
2-download the file twekui98.exe and place it there.
3-double click on it to extract the installation files

4-right click on the file tweakui.inf.  If you don't have windows set to show file extensions, it is the one that looks like a notepad icon with a golden gear on it.  Skip to step 6 if you are installing from the windows 98 CD.

5-after the installation completes, you can delete the power folder.

6-to use Tweak UI, click on start | settings | control panel.
     Open the Tweak UI icon.
7-Click on the tips button for more information.