How to Make Your User Interface Bigger in WoW
One of the many differences between Classic WoW and Retail WoW includes the size of the user interface.
To make your user interface bigger,
1. Click the Game Menu button in the bottom-right corner.
2. Click the “System” button.
3. Ensure the “Graphics” tab is selected.
4. In the “Display” box, ensure the “UI Scale” box has been checked.
5. Drag the UI Scale cursor on the slider to a different value and then click the red “Apply” button. The default user interface’s scale lives somewhere between 0.70 and 0.75.