Getting old settings back

[Bamm]

Yesterday I lost all my settings. I got an error downloading a map:

And now I think it was based on not having enough disk space left  Anyways, I at first thought it might be fixable by downloading the new cod update, so tried that and also got an error. After deleting other stuff, I could download the update and download the map, but all my setting were gone (probably because the update was interrupted), including binds, controls for killstreaks, settings for which graphics etc etc. I tweaked a lot over the years, trying to get my computer to like the game. Like usually it won't be able to get over 125 com fps, whatever that means. After losing my settings that rate dropped to about 50 because my settings had too much detail etc and I became very laggy. Cue a bad bad mood  

So I'm wondering, is there a way to retrieve and put in my old settings? Is there a place where my old settings got saved for example? I also have a manual backup from my computer from before we switched to cod4x where most of my desired settings were in effect. Could I use that in a way?

I will also clean up my computer some more, so ill have more space. 

Final note, I can follow instructions on computers, but I don't have any knowledge of names of parts or programs or whatever, so if you're able to help, please explain in very lay man's terms