There is a debate among the Halachic authorities regarding the proper pronunciation of the Berachot recited over fruits and wine. According to some opinions, the text should be pronounced "Boreh Feri Ha’etz" or "Boreh Feri Ha’gefen," as opposed to "Peri." Meaning, according to this view, the Beracha should be pronounced without a Dagesh (dot) in the "Peh," such that it is pronounced "Feri" instead of "Peri." This was the view of Hacham Bension Abba Shaul (Israel, 1923-1998), in his Or Le’sion (vol. 2, p. 304), who noted the grammatical rule that when a word ends with an "Alef," and the next word begins with a "Peh," the "Peh" is pronounced without a Dagesh.
Hacham Ovadia Yosef, however, disagreed. In his Yabia Omer (vol. 9, Siman 22), he explains that the aforementioned rule applies only when the two words are read together. But in the text of these Berachot, the words "Peri Ha’etz" and "Peri Ha’gefen" are read together, separate from the word "Boreh." As such, the letter "Peh" is pronounced with a Dagesh, and the word should therefore be pronounced as "Peri."
There is a debate among the Halachic authorities as to which Beracha should be recited over cognac, which generally contains wine. Of course, if one drinks cognac which was prepared from a fruit other than grapes, such as figs, then the Beracha is "She’hakol," and if one recites "Ha’gefen" he has not fulfilled his obligation. But when it comes to cognac that is made with wine, we find a debate among the Halachic authorities. Rav Yaakob Emden (1698-1776) ruled that since cognac contains wine, it requires the Beracha of "Ha’gefen" just like ordinary wine. Others, however, including the Hida (Rav Haim Yosef David Azulai, 1724-1807), in his Mahazik Beracha, and the Kaf Ha’haim (Rav Yaakob Haim Sofer, 1870-1939), in Siman 202 (Se’if Katan 15), rule that the Beracha recited over cognac is "She’hakol." In their view, if a gentile handles cognac it does not become forbidden, because its status is not determined by its wine content, and thus by the same token, its Beracha is "She’hakol," and not "Ha’gefen."
Hacham Ovadia Yosef, as documented in Yalkut Yosef (English edition, vol. 3, p. 39; listen to audio recording for precise citation), ruled that one should recite "She’hakol" over cognac, in accordance with the view of the Hida and Kaf Ha’haim, but one who recited "Ha’gefen" has fulfilled his obligation and does not recite a new Beracha. He notes that the common custom follows the view of the Hida and the Kaf Ha’haim, and thus one should follow this practice and recite "She’hakol." Nevertheless, if one mistakenly recited "Ha’gefen," he does not recite another Beracha, as long as it contains wine. Incidentally, it should be noted that cognac may not be drunk unless it is prepared under Rabbinical supervision, due to its wine content.
Summary: The proper pronunciation of the Berachot over fruit and wine is "Boreh Peri Ha’etz" and "Boreh Peri Ha’gefen," as opposed to "Boreh Feri…" The proper Beracha over cognac is "She’hakol," though if one mistakenly recited "Ha’gefen," he has fulfilled his obligation, as long as the cognac contains wine.