The screen properties and the appearance of fonts in Windows applications, including SimUText, are managed in your Display control panel. For most computers, the look of Windows screen fonts can be improved by enabling the ClearType feature. This is particularly true for notebook computers or any LCD screens.
Enabling ClearType to improve font clarity on Windows
Use the instructions in the link below (from the Microsoft support knowledge base) to turn on ClearType on your Windows machine.
http://www.microsoft.com/typography/ClearTypeFAQ.mspx (Select the FAQ for "How do i adjust my ClearType settings?" and follow the notes for your version of Windows.)
Refining your screen fonts even more with the ClearType Tuner (Vista and 7): http://www.microsoft.com/typography/cleartype/tuner/tune.aspx