MrClass wrote512MB RAM bro? You're outta luck buddy. Even Windows XP has an issue running on 512MB of RAM. Go for Ubunto 11. It is different but runs like a charm, no anti virus needed either.
By the way, never run unlicensed software in a school. I am telling you that cause of personal experience. I am an IT and network administrator at a school. Companies like Microsoft and GFI ask for a visit to school premises and you can't say no to them. They WILL ask about the licenses. Thank God we are a Mac environment, the Microsoft staff didn't stay 10 minutes in the school after they saw the Mac lab :P
ill let them deal with that