First off I would like to say thank you to the author of this program for sharing a great tool for burning discs. I was going to reply in some of the other topics about this, but I'm not able to post in them (is my account too new or something?)
Anyway, I would recommend using the NSIS silent installation method if you don't like OpenCandy. Open a command prompt with administrator privileges, browse to the directory with the ImgBurn installer and run this:
SetupImgBurn_188.8.131.52.exe /S /D=C:\Program Files\ImgBurn
This should bypass the offers for third-party software. To LIGHTNING UK: Feel free to remove this post if you don't want users seeing it. The vast majority of people who use ImgBurn will probably never visit the forums anyway.