First, it's not clear how to install VMWare tools, nor if these tools (apparently crafted for Linux) will work under FreeBSD. Second, the screensize seems limited to 640x480, probably because there are no VMWare tools - I'm guessing that these include a new video driver.
VMware tools exist for multiple platforms, including FreeBSD, so no need to try to hack up the Linux tools. If you select Virtual Machine > Install Tools, does FreeBSD see the tools CD? (this only works if you chose the correct OS type during the install, as in SMB's post). If you didn't, you can manually attach the tools image, it lives at /Library/Application Support/VMware Fusion/isoimages/freebsd.iso
I've never used FreeBSD, but I assume that you expand vmware-freebsd-tools.tar.gz and run vmware-install.pl (probably as root).
Edited to reference iso location. -etung 2007.05.31 16:47