The version cannot be seen from within Access Runtime.
To find the version of your Access Runtime you need to go to Windows Control Panel>Programs and Features and look up the Access Runtime or in Windows Vista you can access it from Windows Explorer (ÿ+E) when the Computer is opened via Uninstall or change a program.
You might need to show the Details Pane to see it at the bottom.
Version 2 is having Product version 12.0.6237.1003
Version 1 is having Product version 12.0.4518.1049
Another method is that when it is running look up the process MSACCESS.EXE in Process Explorer and check Properties>Image.
Download to Microsoft Office Access Runtime Version 2.