Firstly I have to say I am little confused, so I will prefer write some comment before answering, but I haven't enough reputation points to write a comment so I will put everything here.
From your pictures I am assuming that you have multiple band aerial imagery. So when you click it with identify you see values like Red, Green, Blue. If you wish to know the gridcode value in your polygon result, you have to firstly combine these values to one single value (i think that the raster to polygon tool is doing this in first step). Bear in mind that result of this would be greyscale raster, so you will probably need to identify your areas with the help of original raster.
Now how to do it. This should work without extensions (at least with version ArcGIS Standard):
click Windows -> Image Analysis
in Image Analysis Window -> check and select your raster -> in processing tab click add function button -> in new popup window right click your raster -> insert ->greyscale function ->ok
this should provide new raster layer with single integer values. Click with identify on this layer and read the pixel value for your area of interest
convert this layer with raster to polygon. The gridcode field of resulting polygons holds the pixel value from your greyscale layer
Hope this helps.