Benjamin,
While I own several guns in this caliber I have never been impressed with the round for use in a defensive role. Many of the guys on this thread will correctly supply you with comparisons to other calibers more accurately than I would, therefore I will leave this task up to them. Bear in mind a few individuals may respond with support for using 22 long rifle rounds for self defense as they have either used it themselves or have heard of others that have used it to successfully down dear sized animals and aggressive individuals as well. Don't get taken or be confused with these responses, know that any round in a given ideal situation can and will be successful in a defensive role, but that is not the question that you are 'correctly asking.' You are 'correctly asking' if the 7.62x25 Tokarev would be "good" for self defense.
With what I have stated above you should be aware that the round has been used by foreign police and military units, but this in itself does not answer your question, as your question included the word "good" for self defense.
Good luck in your future shooting.
JHT