Hi
Just to give some additional information.
If you want to view overall status of your project then
from Project-Project information-click on statisitics.
A new dialog box will appear which will give you overall picture of project
progress and variance.
Also you can save upto 11 baselines, to track project at different stages.
However in Tracking Gantt view you will also see the original baseline.
To view many baselines together you can make use of Multiple baseline gantt.
View- more views- multiple baseline view
Hope this helps