H.P. Stink

I was downloading something from MS and it kept prompting me should it run or not. I chose the option "Always run software from Microsoft" (if you downloading anything you will see the box asking whether you should always run software from this company or not) and now i would like to remove that option and set it back to asking me and not to trust installing software from MS without asking me first - anyone know how this is done? Thank you

Can someone help me. I have HP pavillion 7924 and it doesnt startup i need to use HP's recovery tool in order to restore the computer to its factory defaults problem is the pc wont start and according to HP the tool is on the hard drive (after reading some websites). I dont want to call HP as theres a massive charge to sort this - does anyone know how i can get around this? even if i reformat the drive and use the recovery tools on the hard drive. Your help is mostly appreciated