X68000 is very well supported. Even add-ons like a hard disk and MIDI interface are supported, and the majority of games play fine.
PC98 and PC88 also play many games, and there is some add-on card support for them once again, as well as support for specific PC-98 models. Kale can give details
IBM PC emulation is pretty good, from the original Model 5150 up to 486-33 with SVGA and Sound Blaster or Gravis. DOS, OS/2, Windows 1.0-3.11, Windows 9X/ME, and Windows 2000 all run, in addition to Linux, Netware, and others. Because we emulate the actual machines in their entirety, you do have to do things like configure the BIOS that e.g. DOSBox doesn't require. There are multiple video, sound, Ethernet, and other cards (e.g. MPU-401 for MIDI) supported for ISA-bus PCs.