How to create sharepoint 2010 aspx page in "pages" list using powershell?

Here you have an answer for your question: http://stackoverflow.com/questions/18380019/how-to-create-a-page-in-a-given-sharepoint-2010-pages-library-using-powershell[^].

Two columns layout is already built-in so you can also do it as it is described here: https://myspworld.wordpress.com/2012/08/16/powershell-script-to-change-the-page-layout/[^] and type two columns page layout name.