I have a 17" 4:1 CRT monitor and the default font configuration of Mint 7 KDE was very frustrating, a lot more considering I was leaving Window$ XP which have a good if not the best font quality of all desktop OSes.
Wich I did first was install the M$ Core Fonts then search the net for the "Tahoma" TrueType font which I found -normal, bold, italic and italic bold- download and install it with size 8 AND turn OFF anti-aliasing (I hate antialiasing, why is it becoming defacto standard!?) and set font DPI to 96.
After playing a while, I realized DejaVu is lot more readable and way fewer stressful to the eyes so I go back to standard DejaVu Sans keeping size 8 to everything but "Fixed wide"(monospaced) : Courier New 9 (sorry if misspelled, I have a spanish Mint) and "Windows title" DejaVu Sans Bold 8; this works well for me.
Hope this can help you, regards