Do gay men and straight women find the same parts of a man attractive?

Oh probably, at least in general if not on an individual basis.  Both groups may be attracted to a man's masculine looks, or masculine physique, or a cute butt, or especially what he has to offer in the genitals department.  Each area will have individual differences of course (ie. prefer a bare chest vs. hairy chest, etc.).  You're wrong to think the brains are different.  Medical brain scan studies have shown that in a part of the hypothalamus where sex drive is regulated, there is a similar shape of the structures between homosexual men and heterosexual women, and between heterosexual men and homosexual women.  It is a physiological fact that there is similarity, even if there are other differences such as the particular gay man being masculine while the particular straight woman is feminine for example.

There are no etched-in-stone rules about who has to be attracted to what, or have what personality type and mannerisms, or have what interests and hobbies.  There are straight guys who are masculine and straight guys who are feminine; there are gay guys who are masculine and gay guys who are feminine.  There are straight women who are masculine and straight women who are feminine; there are gay women who are masculine and gay women who are feminine.  There are also androgynous people of all groups that seem neither masculine nor feminine, or a blend of both.  With approaching 8 billion people in the world and many more in the past, there is every combination of every trait that a human can possess in some person somewhere.

No, racism is not a feminine trait; it's a trait of ignorant prejudiced bigots regardless of sex, sexual orientation, gender identity, or personal gender role.  And judging peoples' entire character based on first impressions of how someone looks is an illogical human trait, not just a trait of women.  Rational people know that a person's looks do not define a person's entire character; it's small minded people who are so judgmental, regardless of sex, sexual orientation, gender identity, or gender role.  You're making a lot of assumptions and generalizations here.

You're covering a lot of unrelated topics here.

Arousal is a reactionary event triggered by the stimulation (sight, scent, sound, touch) of an unconscious part of the brain which controls our sleep and breathing. This part of the brain develops in-utero. Sexual arousal is innate.

It is thought that for most people who are attracted to the same-sex that their early brain developed in conditions where the balance of estrogen, progesterone, and testosterone are slightly skewed. These hormones may "balance" in adulthood, but the sexuality doesn't change. Hormones can affect the way you react, but they don't determine if you will participate in a social construct such as feminism.  

Racism is also not inherent, and the root cause of racism is not sexuality. A person who has been  discriminated  against because of their sexuality may become defensive in later life. Conversely, people who are homosexual may be more compassionate to other minority or ostracized groups.