pcheco,
Please share your installation details with us. You can find them from MyEclipse > Installation Summary > Installation Details. Paste them here.
Also let us know on which version of regular Eclipse could you see the “Metrics” option.
The Metrics -> Enable option can be seen when you are in a java perspective (not MyEclipse Java Enterprise Perspective) using the package explorer. Please ensure the same and then right click on the project, select properties and you can find Metrics in the list.
Let us know how it works for you.