Characterized by their rough brown skin and white flesh, varieties such as Butte fall into the dry/mealy end of the texture spectrum. When baked, the thick skin crisps up to create a perfect “jacket” for the fluffy interior. They’re easy to mash and ideal for frying and roasting. However, they’ll disintegrate in soups and stews.
Compared to russets, white potatoes, such as Onaway and Elba have smoother, thinner and lighter-colored skin. Considered all-purpose potatoes, they are creamy when baked yet hold their texture when boiled. If you don’t know what potatoes to use in a recipe, you’ll be safe with white potatoes.
Made familiar by the popular Yukon Gold variety, these potatoes have fine-grained, dense flesh that holds its shape when cooked. They’re ideal for potato salad, soups and stews, but can also be roasted and baked. Carola potatoes also fall into this category.
Potatoes with red/pink or purple/blue flesh are as easy to grow in your garden as any other potato and, if you ask me, way more fun to harvest, cook and eat. All-Blue has dark, purple-blue skin and lighter blue flesh. It is somewhat mealy, making it good for baking. All-Blues keep their color best when baked, microwaved or fried; when boiled, the flesh fades to a grayish blue. Some people think it has a subtle nutty flavor. Cranberry Red, also known as All-Red, has red skin and pink flesh (sometimes swirled with white) with a dense texture that holds its shape, making it ideal for boiling and sauteing. Red Cloud is a red-skinned potato with dry, white flesh that’s perfect for baking.
Like the name implies, fingerling potatoes, such as Russian Banana, are shaped like fingers — small and elongated. They have thin, tender skin (thankfully, because they’d be difficult to peel) and are fantastic roasted. Because they’re so small, you can boil them whole, skin intact, so they don’t absorb as much water as potato chunks, making them great for potato salad, too.
Immature potatoes that are harvested in early summer before they are fully mature (before the vines die back) are called “new potatoes.” They can be any variety. Their skin is thin and tender, and they’re often boiled whole and tossed with butter and fresh parsley. They have a shorter shelf life than mature potatoes.
From http://www.gardeners.com/Potato-Varieties/7556,default,pg.html which also has other interesting potato tidbits.