Here is a tips or tweaks as you say to lock your home page.Type "regedit" in run menu and first save the REG File to your hard disk. Double click it and answer yes to the import prompt. REG files can be viewed in Notepad by right clicking on the file and selecting Edit.Then copy paste the code below to a notepad and save it with any name but the extension should be ".REG".The code is as below :
Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Internet Explorer\Control Panel]
"HomePage"=dword:00000001

[HKEY_CURRENT_USER\Software\Policies\Microsoft\Internet Explorer\Control Panel]
"HomePage"=dword:00000001

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer]
"NoSaveSettings"=dword:00000000 After you save it as mentioned above double click on it and press OK.And it is done.For more information about latest refistry tweaks just subscribe in the email