Cant make a desktop image/wallpaper

Cannot save wallpaper! Please help! Firstly, I have done the obvious control panel/right click on desktop stuff. Does not work. I cannot even choose a ready made theme from control panel, only plain colours. If I choose a theme or browse my own pics, there is no error message, it just does not work! I have even tried registry stuff, like making something available under policies/system/etc. But the 'available' thing was greyed out! This happened yesterday. All I can think of is that I have downloaded a few things, to try to help improve the performance of my video editing program. They did not work. And somehow I got this annoying accuweather thing on the bottom right. Apparantly, this can be spyware so I wanted it off. The advice for this was to uninstall any recent stuff that you did not want or recognise. So I did this, only stuff from the past few days. The result of this was everything on the screen getting bigger! And the problem of wallpaper images. I have managed to adjust the resolution back to normal, but still stuck with wallpaper issue. I was trying to see if I needed graphics software updating, and found something for the intel R HD. But as I said, it did not help the issue I was looking into, so I uninstalled these things. Have also done a registry scan, repair. Sorry write so much, but I want to prevent everyone giving the obvious answers I have already tried! Thanks.

Howard White was added to Windows 7 by Umair Ahmad.

Would love to! But system restore has never worked for me on this machine for some reason. Never offers me any points, and if I create one it goes through it all and then says it has not been able to do it. Can't remember the exact error message but it never seems to do it!

Thanks, but I have managed to sort it out. Here is a youtube link that actually worked! https://www.youtube.com/watch?v=tYaCmuGSbWY I do not understand it, but it did. Basically, go into user files through things like appdata, roaming, and more with hidden files showing. Then I saw my old screensaver picture greyed out (I think) which I had to delete. For some unknown reason, this has sorted out the issue! Hope this will help someone else.