Trojans are malicious applications that pose themselves as legitimate software in order to trick users to install them. Once on the victim's machine, it may run any number of malicious process to steal vital information or inflict damage to other software.
Backdoor.VB.qg is a generic back-door program. Can allow an attacker access to your personal computer.
Backdoor.VB.qg can give an attacker the ability to upload/download files, execute/delete files, change system settings, edit the Windows Registry, open cdrom tray, launch key-loggers or other malicious software.