I am upgrading my Mac Mini G4 from OS 10.4.11 to OS 10.5. I received my Mac used from a friend. He already has Xtools, Mac Ports and Ruby on Rails installed. Will this cause any special issues I need to know for the upgrade?
You will probably like to upgrade any older version software. But not knowing what versions are installed you will need to determine that, then check to see if updates have been released (for third-party) or use Software Update for system updates.
If the OP installs CNET TechTracker, then it will find virtually every application that he has installed and will give him a link to its latest update if there is one. The CNET database of Mac applicaitions is not perfect, but it is an enormous help for those of us who have a fetish about staying current.