Remember you can not create something from nothing.
Thus you can not increase the quality of a file just by increasing its bitrate or sample rate.
The easiest way to visualize this would be taking a small picture like say a 100x100 pixel avatar and trying to increase it to 800x800 to use as part of your desktop wallpaper.
I'm sure you know that the image will get bigger, but it wont magically become a 800x800 image of better quality you will still only have the data and quality of the original 100x100 image.
Same goes with sound files.
You can only start from the top and work your way down. So taking a 800x800 image and shrinking it to 100x100 for an avatar is fine, the image program can methodically reduce the size of the image and remove data as needed.
Trying to add data however like your suggesting is impossible.
Now if you just wanted to change the sample rate for some other odd reason and it was not for quality purposes it would be best to tell use the format the file is in.
If its a common format or if you can decode it to a simple format like .wav you can use Audacity to open it and convert it. Also most video editors should handle it fine like windows movie maker, sony vegas, adobe premier.
The other important thing though is is the format currently lossy or lossless. If its already in a lossy format like MP3 compressing it again will result in loss of quality. If its a .wav or .flac you can work with it at your leisure but the higher sample rate will make the file size larger.