I am Roy from Dell Social Media and Community team.
With regards to your query, try the following steps
Right-click the desktop. Choose "Personalize."
1. Click Window Color and Appearance.
2. Click Advanced Appearance Settings
3. Go through each item and reset fonts (where appropriate) to Segoe UI 9pt, not bold, not italic. (All the settings in a default Windows 7 or Vista machine will be Segoe UI 9pt.)
If this doesn't work -- or I should say, if all your settings here are already Segoe UI 9pt -- then you have probably inadvertently changed your Clear Type settings. Clear Type is how Windows draws fonts on-screen, and depending on the screen, different settings will be needed for optimal font display.
To fix this in Windows 7:
1. Right-click the desktop. Choose "Personalize."
2. Click "Display"
3. Un - Click "Adjust Clear Type Text"
4. A window will pop up. Make sure you uncheck box ("Turn on Clear Type"). Click "Next."
5. Follow the prompts through the wizard, adjusting until the fonts look "right" again.
Kindly revert for further clarifications,
Thanks and regards,
Dell Social Media Responder