If you want ALL your text to be larger you can either increase the font size of increase the DPI.
To increase the font size right click on the desktop and choose Properties.
Choose the Appearance tab.
Choose a larger font size.
Hit Apply, then OK.
To increase the DPI, which increases not just fonts but icons, right click on the desktop and choose Properties.
Choose the Settings tab.
Choose Advanced.
Choose a higher DPI setting.
Hit Apply, then OK, then OK. You may be prompted that a reboot will be needed for the change to take effect.