Set Windows 7 Default Login to a Non Domain Account

We have 12 Laptop Pc's that we have upgraded from Windows XP to Windows 7.
The laptops are used by staff on away days. They log on to a local account on the machine - say User1 with no password.
On the Windows XP Login screen there was a drop down menu allowing them to log on to the Local Machine. However in Windows7 there is no such box and it is confusing staff.
Windows 7 tries to log into the domain by default, it doesn't seem to remember where the user last logged into.

Is there a way to set Windows7 to log on to the local machine by default instead of the domain?
I do not want the staff to have to type for example stafflaptop1\User1 when they log on.

You can use Group Policy (local or domain) or edit the registry directly.

Direct registry edit seems to work best for us. We use a generic script to assign the local computer name, with the variable %COMPUTERNAME%, as the default domain for logon where needed. Run the following:

reg add HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System /v DefaultLogonDomain /t REG_SZ /d %COMPUTERNAME% /f

If using GP look under Computer Configuration, Administrative Templates, System, Logon. The setting is labeled "Assign a default domain for logon". However, entering %COMPUTERNAME% here does not appear to be correctly interpolated prior to the logon display.

If you open up the GPO editor

gpedit.msc

you can edit the option under:

administrative templates 
system
logon
assign default domain...

click ENABLE and the enter "." as the domain name. That should default your login screen, after a reboot, to the "computername", which will authenticate your local accounts by default.

You'll of course have to type domainname\domainaccount or a UPN if you need to log in with a domain account.

Windows 7/Vista and Windows Server 2008 already log into local accounts by default. When you enter a username, Windows sets the domain to the local PC if the username is associated with a local account. If there is no matching local account, then Windows assumes that it is a domain login.

For example, if stafflaptop\User1 and domain.org\User1 both exist, Windows 7 will default to stafflaptop\User1.

You can use .\user1 to log on local domain.

The .\ represent the local domain.

Very useful for Windows 7 and Windows Server 2008 r2.

When connecting to a domain network, but using a local login, the "." in default domain name for logon in gpedit.msc does not change the user name to authenticate locally by default. Whenever I log off the local user to change to the local admin, I always have to type ".\" or I get a bad user name or password error.

Manually entering the "computer name" in the default domain name gpo works, but is a hassle when deploying multiple workstations from a single image, when there should be a default setting.