The syntax for disabling warnings is as follows:
#pragma warning disable 414, 3021
Or, expressed more generally:
#pragma warning disable [CSV list of numeric codes]
Is there a list of these numeric codes and the description of the warning that they're suppressing? Much to my chagrin, I can't seem to locate it via Google.
MSDN has a list of warning codes. Unfortunately, you have to click each link to view what the code actually means.