Hi,
The situation is bad. Whatever my "brother-in-law", not for the lack of a word, put onto my desktop computer has completely crashed the system and the computer will not boot at all now. The last error message seen was just as the desktop appeared. A little window seemed to open and close for a split second (strange never seen before) and then svchost.exe is not a valid Win32 application. The computer froze at that point. After rebooting it never starts. I have tried rebooting in safe mode, a rescue disk. I have also tried to get into the bios to change the booting configuration but nothing!!
My friend, who works for a computer company near here, is helping me. He is going to put the hard drive on to one of his test computers at work as a slave drive (is that correct) to see if that will at least get it started. I'll let you know how it goes.
Thanks anyway for those who tried to help. From what I understand now, it seems that my brother-in-law clicked an allow box to one of the security programs on my computer. One of them blocked this thing. I'm going to put a password onto my computer from now on!!!