Depends on the level of depth of the question. In a free society like ours, the vast majority of the time the heterosexual will want to marry an adult member of the opposite sex. Well over 90%. So for the vast majority of instances, the answer is yes. Homosexuals will nearly always want to marry someone of the opposite sex, and in many places the answer to the second question is therefore "no." I think when you said "want," you didn't actually mean "want." You really just meant "Can hetero/homosexuals marry anybody?" to which the answer in each case would be no. But the actual questions you asked, the answers are generally not the same.