Changing the screen resolution is fine on a CRT but not very good on TFT screens as the native resolution is best, making any change to that is likely to make the displayed data less clear.
You can change the DPI in the windows settings, see image, I have a 26" TFT 1920x1200 and a DPI of 96 is fine for me (with glasses) and relatively small text. The increase the DPI the greater the text size.
Unfortunately that impacts every font used, I don't know too many AVs that have a selective font size when using a fixed GUI.
Though if the user has has sight problems they would want something like this across the board.
Edit, incorrect wording, see italics above.