No I do not think homosexuals should be allowed to marry. Marriage has already been defined to what it is.
I do not think homosexuals should be permitted to adopt kids because this would be short-changing an adoptee of a potential father figure (in the case of lesbians) or a mother figure (in the case of 2 guys.) This would be HIGHLY selfish on the part of a homosexual couple to deprive a young child the opportunity to grow up in a conventional 2 parent home.