It appears that your father was a resident of NY. Although you are a Florida resident the statute of limitations would be passed on his residency. Therefore, you need to repost this question under New York to get the most accurate information for your issue.
This answer does not constitute legal advice and does not create an attorney client relationship. The answer is for information purposes only and is based on the limited information you provided. If you would like to discuss your Florida legal matter further please call my office at (904)353-0033 x 14.
Real property ownership and succession are generally governed by the laws of the state(s) in which the property is situated, so you should consult counsel in New York and Georgia to gain a full understanding of your rights. That being said, if the New York property was titled jointly to your father and his wife, it likely became her sole property on his death. Similarly, if the Georgia property had all three names on it (yours, your father's and his wife's) then you probably own an undivided one half interest in the Georgia property as a tenant in common with your stepmother. Normally cotenants would be equally responsible for the payment of taxes and other charges to the land, but if the taxes aren't paid then the property will eventually be sold to pay the delinquent taxes and you will lose any interest you may have. One option you may have is to pay the taxes yourself and then sue your stepmother in order to partition or divide the property. In connection with that suit you can get credit for any payments you made that she should have made, such as one half of the taxes. However, would not advise anyone to pursue partition of real property without a lawyer's help. Good luck.
This answer is for general purposes only and may not be relied upon as legal advice. No attorney-client relationship is established by this answer.