I found this setting 2 days ago, was happy to get rid of the pale blue.
You can also set the theme colors in Excel, Outlook, Access.
But not in Onenote 2007
Computer type PC/Desktop System Manufacturer/Model Number COMPAQ Presario OS Windows 7 Ultimate x64 CPU AMD Athlon 64 X2 Dual Core 3800+ Memory 4 GB Graphics Card ATI Radeon HD 6450 Monitor(s) Displays Samsung SyncMaster XL2370HD, ViewSonic VA1912wb Screen Resolution 1920*1080, 1440*900
Keyboard Logitech G15 Internet Speed Slow... (DSL Lite) Antivirus Microsoft Security Essentials, MalwareBytes Browser Firefox (lastest stable) with NoScript Other Info Just a humdrum little system.