To Uninstall Powershell 1.0 through a workstation like windows XP, you must remove it with "add/remove a programm".
To see it on your programm list, you can verify if you selected "View Updates".
As usual, you can desinstall with the UI,
Programm will check your current configuration with common files,
You will be able to review all programm concerned for deletion.
Continue by selecting "Yes".
When done, a popup will let you know the end.
Always check your source disapear.