After listened to some podcasts about Lion installation, I decide to test out the DVD disk I made while I installed Lion to my Macs. According to the information I received from all the resources, the bootable disk should be burned from Disk Utility tool. Therefore, I am not sure if the DVD I burned directly from Finder to DVD is bootable or not. I have to test it out by restarting my Mac.
It approved that my way to burn dmg file is not the right way. I could not find out my DVD. During the restart process, the boot selection is turned on when the option key is pressed. However, I found that there was two disks to boot: my Mac Lion HD and a Recovery HD. I have never seen this Recovery HD before. I think that Lion creates a boot disk in my HD. Since there is no disk available for Lion installation, there should be a way to boot in case of HD repairing. Now I recall that Snow Leopard recommends to use the original disk to boot and to use the Disk Utility tool to verify and repair HD.
To verify the Recovery HD is really a Lion boot disk, I started my OS from the Recovery HD. It is a Lion boot HD. Here is the entrance of the startup:
Here is the menu item of Utilities:
Here is the Disk Utility. As in the window, Disk 1 contains a Mac OS X Base System:
I copied my Lion dmg file to my desktop and then followed the correct instruction to burn my Lion dmg file from Disk Utility app. Now the new DVD is bootable. Here is my second try of restart with boot disk selection:
I verified the DVD disk by selecting it as start. It took several minutes, maybe 10+ minutes to load start files. The DVD media is just too slow to start up. That's why Apple does not like optical disk at all. It is just like floppy disk ten years ago. It is time to retire DVD/CD media.
After all these tests, I am back to my Lion. The new log in window is very different from the previous one, and I like its simple interface. One thing I realize is that the resume seems working when I log in: all the previously opened windows are resumed. Another thing I noticed that re-log in after sleep or lock is much faster than before. It takes less than a second to bring me back. I remember that Snow Leopard takes several seconds to resume network connection, specially when Safari is opened. Now everything is back instantly.