Which website did you use to attempt the download? I'd recommend using
File Hippo to do the download.
The current version of Imgburn (2.5.8.0) uses Open Candy in the installer and is set by default to install other software along with Imgburn. Imgburn 2.5.8.0 is safe provided you don't accept any default or express installation options and explicitly opt out of each of the so called offers. See the link in my post above for more information.
If the current version is still being rejected, try downloading the previous version. On the File Hippo site, the older versions will be listed on the right side of the page. version 2.5.7.0 should be fine. The older versions do not contain Open Candy in the installer. The installer will still ask you to install other things such as the Ask Toolbar for example. Be sure to read the options presented by the installer and opt out of everything except Imgburn.