Problem with hidden files...

i have this problem with hidden files on windows 7 x86 rtm...
whenever i select the option 'Dont show hidden files and folders' i see hidden files and whenever i select 'Show Hidden files' i dont see hidden files...
and in no case i see the 'hidden protected operating system files'...

i have no virus problem on my pc...maybe some program changed registry...i tried changing the registry keys which are related with hidden folders...but still the two options remain interchanged..

please help me if someone knows any solution...thnx

thanks for the quick reply...i dont want to lose any data on my current install...so will give the repair install a try instead of formatting...

one more question....in repair install it saves the original install in a Windows old folder...i have a 50 GB system partition...out of that 25 gb is used already...so when i repair will it use the other 25 gb also(or maybe setup cannot continue due to low space) considering that old files and folders are backed up in windows old folder..

thanks shawn...will try to repair whenever i get time...

@zigzag3143
yes i was mentioning about those folder options...i have x86 rtm...clean install..

i did a repair install and the problem is now rectified...also few other software issues which i had were also resoved by this....thanks again for your help..