MobaLiveCD
Not only will it start bootable CD ISO images but with the last update to version 2.1 you can also launch a bootable USB flash drive which is useful when you’re testing if your multi boot or installation USB works before trying it for real. MobaLiveCD is simplicity to use, all you have to do is run it (Run as administrator if you have UAC on) and either press “Run the LiveCD” and browse for the ISO image file, or click “Run the LiveUSB” and choose the letter of your flash drive.
The program will then launch QEMU with a predefined configuration and begin the boot process. To interact with the emulated operating system, click in the window, press Ctrl + Alt to get out again. The “Right-click menu” button usually doesn’t work in Windows 7 or 8 because they recognise the ISO file type by default and already have other programs associated with it, Vista and XP will work if their ISO file type hasn’t already been taken over by another program
Also, because there has been no updates since 2009 it will sometimes fail to boot an ISO image or USB flash drive correctly, likely due to a now rather outdated version of QEMU. MobaLiveCD is still compact and useful but its mileage depends entirely on whether you can get it to work, an update would definitely be welcome but sadly the project appears to have been pretty much abandoned.