Enables user notification of user input for interactive services, which enables access to dialogs created by interactive services when they appear. If this service is stopped, notifications of new interactive service dialogs will no longer function and there may no longer be access to interactive service dialogs. If this service is disabled, both notifications of and access to new interactive service dialogs will no longer function.
From the sounds of that description, I don't think Microsoft knows what the service does. I say disable it.
Default Vista Home Basic: Manual
Default Vista Home Premium: Manual
Default Vista Business: Manual
Default Vista Ultimate: Manual
Safe Setting: Disabled *
Service Name (registry): UI0Detect
Display Name: Interactive Services Detection
C:\Windows\system32\svchost.exe -k netsvcs
Account: Local System Account
What service Interactive Services Detection needs to function properly:
What other service require Interactive Services Detection to function properly: