Both good for me, eyes are most important for me in these shots and you've captured both well
Stephen - I too like the juxtaposition between the images, and in particular I like your desaturated approach to the processing in the first image.
You have a few specular highlights in the skin on both images, I'd look to reduce these in post (but not eliminate entirely, as they add shape). The second image is a bare flash from the looks of things, giving you hard shadows. I personally try to avoid these by bouncing light or using a modifier. I have a tiny soft box that can go on my flash, be held off camera and fired via Nikon's CLS system, and for out and about this works well for me.
You have proved that you can take a picture. Re-shoot with proper backgrounds...esp. your Dad.
Steve - you have two nicely crafted portraits here. I definitely prefer the second, but that has a lot to do with your choice in PP rather than the composition itself.
I understand why you wanted to downplay some of the clutter in the image, I just find that what you've ended up with is something that is neither coloured nor B&W, but rather something in-between and in this case your father seems to have developed a rather unhealthy looking colour. I think going to pure monochrome would result in a better looking image. That doesn't mean you should avoid desaturation, as I sometimes use this technique in some of my work, but I tend to be quite subtle when I do and slightly reduce the saturation to hide underlying skin tone issues, so the degree I would use is very much less than you have here.
I like both of these images but I will tend to clone that light in your father's face to the nearest pixels.
Stephen, I especially like the candid pose you have captured of your father.