This script runs on Windows PowerShell 1.0, and PowerShell 2.0  and will change the start mode of a service. You will need to change the comptuer name and the name of the service prior to running the script. Because the script uses WMI to work with the service, you can target a downlevel computer system such as Windows 2000 that cannot run Windows PowerShell. Only the computer that is running the script needs to have Windows PowerShell installed. To run the script you will need to have Administrative Rights to change the status of a service.

# ------------------------------------------------------------------------
# NAME: changeStartMode.ps1
# AUTHOR: ed wilson, Microsoft
# DATE: 9/14/2009
# KEYWORDS: WMI, Win32_Service, ChangeStartMode, Method
# COMMENTS: This script changes the start mode of the bits service
# and evaluates the return value to see if it was successful. 
# ------------------------------------------------------------------------

$wmi = get-wmiobject -class win32_service -namespace root\cimv2 -computername lisbon |
where-object { $ -eq 'bits' }

$rtn = $wmi.changestartmode("manual")
if($rtn.returnvalue -eq 0) { "success" }
  { " $($rtn.returnvalue) was reported" }