Seriously, it is great. Dosbox is okay, but this allows for many none DOS programs as well. It is kind of a pain to setup the first time, since you have to install Windows on your virtual PC and everything. But once you get it setup, it is flawless. Also, once you get ti setup, you might as well save all the files to a DVD-R, you can save your virtual hard drive to the disc and have everything setup just how you wanted, installed programs and all, that way you never have to mess with setting up windows on it or installing your games again. Really a great program for people like me who have a hard time giving up the past.
The last time I used it was to play Resident Evil 2 for the PC. It runs fine on modern PCs, but you cannot save your progress, since the save system only supported FAT partitioned harddrives and cannot recognize NTSF at all. Looking around on the internet, most people recommended a floppy disc or a flash drive, I couldn't get either to work, so I decided to whip out Virtual PC and make myself a brand new Virtual computer with a FAT harddisk. Worked perfectly.