Last month I had problems getting programs to open which with help from here turned out to be a borked OS which System File Checker found and repaired.
Since then she has been running fine till the last few days, now she has started to freeze when running Office 2007, Photoshop, Minecraft and steam

My computer is fully updated, virus and malware scanned and defraged, disk checked for errors. With the trouble I've had recently I would probabely be better doing a clean reinstall but to be honest I don't really want to do that except as a last resort.
Any advice would be appreciated.