The advantage of scanning in safe-mode will allow you to have a "easier" time cleaning. Running in safe-mode doesn't necessarily mean you're going to detect 20 more viruses.
Q: Why canÂ´t I use the boot-time scan? That option is greyed out in the menu!
A: Boot-time scan is available on NT-based Windows systems only (Windows NT, 2000, XP, 2003 and Vista). Also, it is currently not supported in 64-bit operating systems.