Windows 7 or Windows Server 2008 R2 logon delays

Consider the following scenario:

• You have a computer that is running windows 7 or Windows Server 2008 R2.
• You set a solid color as the desktop background.
• The Desktop Window Manager Session Manager service is running.
• You log on to the computer locally.

In this scenario, the Welcome screen is displayed for 30 seconds during the logon process.

So if you like a plain desktop, its not necessarily what Microsoft thought was the case.  One of the reasons why you might face the issue of delayed logons can be that you have chosen a solid color for your desktop.

see the following link for more details and a hotfix.

http://support.microsoft.com/kb/977346