ImgBurn (pictured above) Since most of my recording tasks involve ISO files or burning entire folders as a backup, ImgBurn has become my app of choice. It's small and easy to use, and I've yet to produce a coaster with it. It's also a great tool for creating ISO files - either from a disc or files and folders on your PC. ImgBurn also gets bonus points for the random comments that appear in status bar. See the rest after the jump!
CDBurner XP If you prefer a more Nero-style experience but can do without all the bloat, CDBurner Xp is a great option. Apart from burning pretty much any kind of project, you can also use CDB to create covers and burn Lightscribe artwork to your discs. It also now supports Blu-ray and HD-DVD formats. It's very easy to use even for non-technical types (read: I install this on my friends' and parents' systems). InfraRecorder InfraRecorder has been part of the Portable Apps suite for a long time, and with good reason. It's an excellent burning application that can handle just about any type of project. It is, of course, totally portable so it's a perfect tool to cart around on your flash drive. Running 64-bit Windows? There are also native x64 versions of both the installer and portable versions of Infrarecorder. You've gotta love the "Smoking Aero" demo video - check it out on their screenshots page.
NCH ExpressBurn ExpressBurn packs a lot of functionality into a sub-400Kb download. In addition to creating data and audio discs and ISO files, it can also copy discs and burn video DVD and Blu-Ray/HD-DVD data discs. Volume normalization is supported on audio CDs. Burn CDCC If you just want a tool to burn ISO files, this is as simple as it gets. Burn CDCC is portable and supports CD, DVD, and Blu-Ray image files. It's totally portable and only takes up 150Kb of disk space. Browse for your ISO, choose the burner you want to use, and press start. That's all there is to it.