Your clarification means a lot -- "baked" potato in the U.S. tends to be a whole potato cooked on its own, where the insides become fluffy and creamy, and is done with larger starchy white potatoes, or sweet potatoes work well, too.
Roasted potatoes, on the other hand, tends to be (in the U.S.) be smaller "new" potatoes, waxy potatoes, or even larger starchy potatoes cut up (eg, 'oven fries').
The starchy potatoes only really hold up well when roasting if it's very high heat or a short amount of time -- if you're going to be cooking them with the roast as there's going to be moisture in there, I'd go for a waxy potato (eg, Red Bliss).
As for the browning -- probably coat them well with oil, and if they're not brown enough for your liking when you pull the roast, as you're going to have to rest it anyway, drain the meat juices, crank the oven up to somewhere around 450F (230C) and leave the potatoes in for a few extra minutes.
ps. yes, I know a sweet potato isn't a potato. And I also tend to use Yukon Gold for just about everything, as it makes great baked potatoes, and roasted potatoes (although, not sure how well with a roast at the same time) and they're good in pot roast and stews if you don't add them too early.
There definitely is a difference in flavor, although it is rather subtle. I find that the blue potatoes are a touch richer or more "potato-y" than Yukon Golds. However, in cooking with them I've had plenty of success doing direct substitutions. Other than the blue color being a little odd-looking in some recipes I think you'd be safe just swapping one for the other in most cases.
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Well, from those lists anyway, I think you've overlooked shape and size.
The "pan-frying" potato list is largely of varieties of round potatoes and/or rather small potatoes. They won't produce very satisfactory french fries because of the simple fact that they aren't very big. Or, if they are big and round, you're still bound to get a lot of very short fries when slicing near the edges.
For "french fries" you want a potato that's somewhat large and long. Or at least oblong-shaped, so you don't end up with lots of clumpy short fries. I'm assuming that for "pan-fried" potatoes, the site your list is from considers that you might dice them or make them into shapes other than long, thin strands.