These statements are all found within the Qur'an; the verses stated by menjah below are some of these verses, but, of course, taken out of context and omitting the explanation of such statements.
4:3: " marry those that please you of [other] women, two or three or four. But if you fear that you will not be just, then [marry only] one or those your right hand possesses. That is more suitable that you may not incline [to injustice]."
Polygamy is allowed only if the man is able to be just to all wives and financially support them all. The first wife has the right to object if she does not approve of her husband taking another wife. Also, there are numerous other verses that command men to preserve the chastity of slaves or women if they refuse to have sex. There is NO COMPULSION in Islam.
4:34 is correct; not sure how you can debate this. Men are stronger (physically), and are obligated in Islam to provide for the family. The woman has an obligation to appreciate the man's contribution to the household, and pride or "rebellion" should be punished; much in the same way that a man who does not appreciate the woman's work should be punished as well:
14:7: "Ã¢â,¬oeAnd [remember] when your Lord proclaimed, 'If you are grateful, I will surely increase you [in favor]; but if you deny, indeed My punishment is severe.'Ã¢â,¬Â
4:15: "Those who commit unlawful sexual intercourse of your women - bring against them four [witnesses] from among you. And if they testify, confine the guilty women to houses until death takes them or Allah ordains for them [another] way.
4:16: "And the two who commit it among you, dishonor them both. But if they repent and correct themselves, leave them alone. Indeed, Allah is ever Accepting of repentance and Merciful."
Women who commit adultery should not be allowed to leave the homes unattended there after, and both are dishonored unless either repents. Is there something wrong with that? Family is one of the most important things in Islam; a woman who cheats on her husband (and a man who cheats on his wife) brings into question the paternity of children, tears apart the family, shames and stresses family and already-born children, and encourages acts of lewdness among others.
"I shall not lose sight of the labor of any of you who labors in My way, be it man or woman; each of you is equal to the other (3:195)"
""O You who believe! You are forbidden to inherit women against their will, and you should not treat them with harshness, that you may take away part of the Mahr (bridal-money given by the husband to his wife at time of marriage) you have given them, unless they commit open illegal sexual intercourse. And live with them honorably. If you dislike them, it may be that you dislike a thing and Allah brings through it a great deal of good." (4:19)