Windows Starter Edition users do not have access to Aero on their PCs
Some extra info:
Hardware Check' before you turn on Aero =>
Windows 7 requires the following hardware in order to enable Aero:
DirectX 9 acceleration
WDDM- compatible driver
128 MB of graphics memory
Pixel Shader 2.0 with 32 bits per pixel support
Windows 7 Starter does not include:
•Aero Glass, meaning you can only use the “Windows Basic” or other opaque themes. It also means you do not get Taskbar Previews or Aero Peek.
•Personalization features for changing desktop backgrounds, window colors, or sound schemes.
•The ability to switch between users without having to log off.
•Multi-monitor support.
•DVD playback.
•Windows Media Center for watching recorded TV or other media.
•Remote Media Streaming for streaming your music, videos, and recorded TV from your home computer.
•Domain support for business customers.
•XP Mode for those that want the ability to run older Windows XP programs on Windows 7.