I would download the latest version of VMware Fusion 5 directly from VMware's web site, getting and using the free 30 day trial.
Uninstall VMware Fusion 2.x.
Upgrade to OS X 10.6.8.
Install VMware Fusion 5.x.
Run a VM and when prompted to upgrade hardware compatibility do so and then once at the Windows Desktop VMware Tools should automatically be updated to the latest version however if it doesn't update automatically then do it manually.