Astroburn (free for personal use, $15 for business users) is a fairly robust file burning program, with some useful features for those who regularly burn a lot of different data sets.
The general interface for Astroburn is extremely straightforward: You use the mini-explorer window in the bottom half to locate files (you can also drag and drop them from Explorer itself), you rename, move, or delete files in the upper window until you have the setup you want, and then you click the "Burn Project To Disk" icon located in the toolbar. To this extent, Astroburn doesn't offer more functionality than Astroburn Lite (though the built-in file finder is a nice touch and the interface is, overall, more informative and flexible), but fortunately, Astroburn has some features that neither its Lite counterpart nor the built-in Windows burner possess.
Most important, Astroburn allows you to save projects (as .brn files). This is extremely valuable if you regularly burn different sets of data--for example, you have several sets of client data you send out every month on CD, or if you regularly back up specific directories to different disks. The ability to save and reload specific sets of files and settings is quite useful.
Speaking of settings, Astroburn gives you a few options, including the ability to burn a CD with only "8.3" file names--handy if you need to pass data on to people running older systems. You can also burn or create .iso files, or duplicate an inserted disk.
Astroburn's help system is located online, so you will need an active Internet connection if there's anything you need help on. It should also be noted the Help pages are fairly ad-heavy, though not to the point where they become unreadable.
Overall, Astroburn provides a good deal of functionality for a fairly low price. It has fewer features than some low-cost competitors, such the $25 DeepBurner Pro, but at $15 for business users, it is also cheaper--and for non-commercial users, it's free.
Note: Astroburn's installer will ask if you want to install their browser toolbar, change your default search engine, or change your home page. These are all selected by default; odds are good you will want to deselect them. This program is free for non-commercial users only. Business users must pay $15.