Bold fixed width font for text entry boxes

In my WinXP, for fixed width fonts, Mirosoft has provides only very light weight fonts and my old eyes need much higher contrast. I would appreciate help in finding such a font. It would have to be one that would fit the Microsoft program. Where should I look? Where can I see what it looks like and how to be sure that it is fixed width?
What question should I be asking that i havn't?