Consult a probate attorney. You will need legal advice and maybe legal assistance to sort out what is yours from what belongs to his wife.
You didn't mention whether he had a will, or whether he or his wife were legally separated or had filed for divorce. Any of those could have an effect on things. California is a community property state, in which everything a man and wife own or owe is legally presumed to be equally the property of the other partner, and in which the property of the one who dies passes to the one who survives.
When someone dies, his bank accounts are normally frozen until the bank receives advice from the court or from the executor, or both. If you and he shared the bank account, his wife will have a claim against some or all of the funds in the account, since she was still his wife. If you claim that some of the money in the account was yours, it will be necessary for you to show records that establish what portion of the account should be credited to you.
It will be the responsibility of the executor of his estate to file his income tax returns for 2007, and if there is a refund, that will belong to his estate. If there is no executor, the probate court may appoint one or his wife will, by default, become the executor. If his tax return for 2007 is not filed, and he owed money to the IRS or to the California Franchise Tax Board (for those who do not live in California, the FTB is our state taxing agency), his wife will be responsible, since they were still legally married.
What happens to the timeshare depends upon who owned it prior to his demise. If you and he owned it as partners, then his wife will be entitled to his share. If the ownership is fuzzy, and not clearly defined, she might be able to get it all.
Lawyer. Long hours, but not as bad as Doctor. Lawyers can schedule things. Docs can't schedule when emergencies or epidemics happen.