When you are in Volunteers the list of names displays with a colored background. Likewise in Schedules, the highlight will color the days that are scheduled.
The setting in Windows XP is reached from a blank spot on the desktop.
Right-click Desktop | Properties | Appearance tab | Advanced button
Click on Color 1. The choices are too bright for a background, so click Other .
You can slide the Hue arrow up to a paler color.
Click Add to Custom Colors. OK.
Back on the Advanced Appearance screen click OK.
But on the Display Properties screen click Apply so that you can see how it looks but still keep this screen open.
Back in the Reporter you may have to close the current window and reopen it to see the color change.
Here are some of the places that newly chosen color will display.
Close the Display Properties window by clicking OK.