Task Manager: easy and incomplete
For more details, see Windows 7 memory usage: What’s the best way to measure?
While I am sure this gives you more granular data......your inititial comment is misleading....the easiest display of memory usage would have been to have the Windows CPU/Memory gadgel always open. Yes you do not get page files and committed memory but why not compare both methods. I am using the gadget and I assumed the data/reading is the same under task mgr-memory usage