创建bat或脚本文件以删除文件

I would like to know how to create a bat file which on its first run would store the system date and on subsequent run delete a particular file 30 days later.I think if a bat file can be created that would store system date on its first run and the second bat files reads the first file for the date would be better.But how?I would like to know how to create a bat file w