Firstly, you need to decide on a method of storing the values, depending on the scope & persistence you're looking to obtain.
For example, if you were to assign the values obtained through the dialog interface to global variables (or perhaps a single global variable containing a list of values), the variable would be defined within the document namespace and therefore the values would be accessible from the active drawing and would persist for the duration of active drawing session.
Alternatively, if you want the values to persist beyond the active drawing session, you could opt to write the values to a file (e.g. a text file [.txt/.ini/.csv/.cfg]) and read such file on the next execution of the program (indeed, this is the approach that I follow with many of my programs). Finally, If you're only looking to store one or two values, the Windows registry can be a convenient location, as you can read/write from/to the registry using the in-built getenv/setenv functions.