First, you haven't posted nearly enough information for our experts to be able to assist you in any specific way. We would need to know a bit more about your system. What version of Oracle are you on? What kind of backup was taken? What has been tried? What were the problems?
If you are using RMAN, there is some good information here:http://www.dba-oracle.com/concepts/rman_re...base_spfile.htm
Additional pages on restoring your database are available here:http://dba-oracle.com/googlesearchsite_pro..._spfile.htm#913
If you're not the DBA, you should talk to yours. If you are, you should call us. 800-766-1884. We have experts that can help, especially if you're in a 24/7 situation.