Using Explorer's Search look for all instances of the Word template file
normal.dot and rename them normal.bak and then retry opening Word.  If
that solves the problem a new default template file will automatically be
recreated and you can delete the files you renamed.

For more details of this suggested fix see MS KB 307814 - "WD: Error
Message: System Is Dangerously Low on Resources"
(http://support.Microsoft.com?kbid=307814).