I was told about All in One repair by a friend, because my Windows XP netbook couldn't run automatic updates, svchost would max out the processor the whole time, making the computer unusable. Windows Repair fixed it immediately, I wish I'd known about it before spending weeks searching for a fix!
Spurred on by this, I tried it on a Win 7 netbook with frequent, random, crashes, with instant success. Then followed another XP laptop which wouldn't reconnect to WiFi after system standby, again fixed, then finally a desktop, Windows XP, which wouldn't recognise anything plugged into the USB ports, this was also successfully sorted.
So warmest thanks from me, my Wife, and two friends!