Our company, with over 4000 users and many high security storage needs, is still on Windows XP so I do not think you will have a problem.
MS will provide security updates for Win 7 until 2020.
FWIW, I have concerns as expressed above about Linux but I would take it over the current incarnation of Win 8 in a heartbeat.
With the low cost upgrade til Jan. 31, and support for XP running out next year(?), then they might be smart to upgrade now. But see post 73 above.