...Free software for Windows and OS X

Main free applicatiosn for Windows:

http://www.filehippo.com

for Mac OS X

http://www.versiontracker.com/macosx

(select License = Freeware)

Dual screen in Ubuntu (ATI card)

sudo aticonfig --initial=dual-head --screen-layout=above

this will go back to normal:

aticonfig --initial --input=/etc/X11/xorg.conf

If it does not work, reboot in recovery mode and select fix X display

Install Samba on OS X

Samba is an open source project that is continuing to develop a freely available implementation of the SMB and CIFS protocols. Since it's open source, volunteers and computer enthusiasts collaborate to develop the software. You can read more about the Samba project on their website, http://www.samba.org.

Follow these instructions

http://macs.about.com/od/macwindows/ss/sharemacfilesxp.htm