1. You can apply for naturalization since you are over 18 years of age.
2. It's 5 years from the date on your green card, less 90 days.
3. See below for USCIS processing times.
(213) 394-4554 x0 Mr. Shusterman is a former INS Trial Attorney (1976-82) with over 35 years of immigration experience. His response to your question is general in nature, as not all the facts are known to him. You should retain an attorney experienced in immigration law to review all the facts in your case in order to receive advice specific to your case. Mr. Shusterman's statement above does not create an attorney/client relationship.
The USCIS has published an excellent booklet titled "A Guide to Naturalization" http://www.uscis.gov/files/article/M-476.pdf that provides answers to your questions and explains the requirements in detail.
Your Q1 answered page 17
Your Q 2 answered page 7 Booklet Q and A number 5
Your Q 3 is available using the USCIS local office listing http://www.uscis.gov/portal/site/uscis/menuitem.eb1d4c2a3e5b9ac89243c6a7543f6d1a/?vgnextchannel=e39c0b89284a3210VgnVCM100000b92ca60aRCRD&vgnextoid=e39c0b89284a3210VgnVCM100000b92ca60aRCRD
Legal disclaimer: The statement above is provided by CC Abbott is based on general assistance and not intended to be a legal opinion because not all the facts are provided. The person requesting information and all others reading the answer should retain an attorney who is permitted by the state bar within the jurisdiction who can examine the complete facts and provide a legal opinion on your case. All information provided in the above answer and other information provided by CC Abbott does not create an attorney/client relationship within any state of Federal law.