Sounds good in theory... except see my other thread about my CD burner no longer burning CDs. It will burn DVDs, however, so I have burned it to a DVD and will see if I can boot off of that.
It'll work just as well with a DVD instead of a CD.
I have an old memtest.exe file in my utilities folder that I ran, it made three passes with no errors, but of course it wasn't checking memory in use by Windows, and I'm not at all sure it was looking at all four gigabytes of RAM.
Yeah. You should boot off the disc if you can for the reasons you stated.