Could anyone confirm if this sentence corresponds with the English one? I have doubts about "dog in the manger attitude".

I think it's not wrong. Maybe the English should be written "he had a dog-in-the-manger attitude" or "he was a dog in the manger"?

Does 底意地が悪い has the same meaning and feeling as "dog in the manger"? My dictionary suggests something like "spoilt/evil to the very marrow of one's bones". The phrase "dog in the manger", of course, can't be said about a kind and virtuous person but that person is not just 悪い or, say, 意地悪, his nature is prevent others to use something he owns but can't use himself.
I've found an expression "宝の持ちぐされ" in my dictionary. Does it match "dog in the manger"?

I'm not sure.... "底意地が悪い" is not part of my active vocabulary.
I have a feeling that this English sentence is not very good anyway. Does the Russian sentence sound natural?

"宝の持ち腐れ" is much different. The point is not on the ill nature. We use this phrase to say it's もったいない.
See: http://tatoeba.org/eng/sentences/show/217264

> Does the Russian sentence sound natural?

Yes, Russian sentence sounds pretty natural and matches English quite well. We have a direct analogue for the "dog in the manger" idiom. According to Wikipedia, it originates from a Greek fable. Please, take a look at the article: http://en.wikipedia.org/wiki/The_Dog_in_the_Manger
I've also found some Japanese examples here:
http://ejje.weblio.jp/sentence/content/manger

So this sentence implies that the wife was "useless" to the old man himself?

Ah, Saitō Hidesaburō sensei! His dictionaries are famous for the excellent examples.
Yet I still doubt that "宝の持ち腐れ" can be used as a translation of this phrase. Can you think of a specific example?

> So this sentence implies that the wife was "useless" to the old man himself?

Yes, that's the point, I think.

> Can you think of a specific example?

The problem is that I don't know all nuances about 宝の持ち腐れだ. is it about wasting a treasure literally, i.e. about wasteful behavior? Or is it about "sitting on money", i.e. possessing a treasure but not making any profit of it?

後者です。「宝を持ったまま腐らせてしまう」ということです。
http://tatoeba.org/eng/sentences/show/2244810

Do I render this sentence right: "Having such a reflexes and not going in for sports is just letting your talent go to waste." ? If so, 宝の持ち腐れ doesn't feel like "dog in the manger" for me since reflexes are something that only their possessor can use. They can't be passed to other people so no one but their owner can make a profit/use of them.

You get it almost right. ("運動神経" means athletic ability here.) So even if "宝の持ち腐れ" could be translated as "dog in the manger" sometimes, that must be a limited case.

It seems that we have two main cases when talking about something a person possesses but doesn't make use of. If this is something that can be passed to other people (money, goods, etc. for example) than we can translate 宝の持ち腐れ with "dog in the manger". And if this is something like a physical ability, a talent, or any other thing useful only for its owner, than we'd rather translate it with "let one's talent go to waste" or other expression about wasting things.
What do you think?

I found the exactly same classification here.
http://dictionary.goo.ne.jp/leaf/jn2/135580/m0u/

Unfortunately, you can't always translate "宝の持ち腐れ" with "dog in the manger" even in the first case. See this example.
http://tatoeba.org/eng/sentences/show/2250322
You won't say "I am a dog in the manger", right?

As I said before, when you say "宝の持ち腐れ", the point is that it's もったいない, while in "dog in the manger", the emphasis is on their selfishness and meanness, I guess.

> http://tatoeba.org/eng/sentences/show/2250322
> You won't say "I am a dog in the manger", right?

You're right, this is not the case, I reckon. And I also doubt that anybody will ever say "dog in the manger" about himself other than in humorous way. :-)