My question is regarding a best cd/dvd burner, freeware or shareware.?

Which is the best CD/DVD burner from all aspects, like flawless burning, multisession ability, variable burning speed etc. I used Nero 8 but a few folder in my dvd did not work and even resulted in pc being hanged, some files taking very long time to open. I have a made a date dvd with data, audio, video, fonts, etc. all mixed. Any suggestions ? For burning operiating sys, we need to select a low speed to avoid any errors, especially in boot cd/dvd. So which is the best burner from all these angles?