How to hide old shutoff valves in bathroom?

Attach two nice knobs

Are you sure they're not the type that use a "key" instead of a knob? Anyway, you really should have functioning shutoff valves, so get them restored if they're not working.

Here is a picture:

http://img839.imageshack.us/i/20110501135052medium.jpg/

I went to other apartments and they have the same thing sticking out from the wall.

Maybe a little child/animal-safe footlocker for toxic cleansers and other yucky stuff?

mynycse how did you find that picture? It doesn't seem to have a label or caption for it. There is not a brand name on it. Why don't you just ask the super in your building, since water is a building wide resource that he and the managing agent are responsible for.

Measure the diameter of the stem. Take the collar thing to the hardware store and get two new one-piece ones of the same size. (You don't need two-piece opening ones.) Get two new round handles that'll fit on the stem. (The oval kind might not hide enough of that thicker part.)

That's how I'd do it, blowing half a day running around between hardware store and Gracious Home....

nwt is right--dont buy the kind of collar shown in the picture--buy a one piece and nice handles--the two-piece opening ones are for situations where you need a collar and cant remove an old handle (frozen on) in which case you paint the beat up old handle and use the two-piece collar