I found this link on how to Repair Windows using the startup repair tool, the most important part is Step 4 you need to click the Repair Computer and not the install now...
https://www.lifewire.com/how-to-perf...dows-7-2626170
If you don't feel confident in doing this or don't have a Windows 7 Disk, Use It Computers in Rishton should be able to help.