|I would suggest you consider one of two paths. One is a virtual machine. Many newer systems fully support VM's. Any processor above maybe an Athlon II 250 with 4G would do fine. Then you could load and run all sorts of VM's at the same time.See VMware's virtual market place for pre-build machines.|
Second would be almost any system made in the last 5 or 8 years. Might be slow but you only need it to set up practice labs.
Might see if you can get the 70-29x books. Some come with a 2003 disk for testing.
Playing to the angels
Les Paul (1915-2009)