Windows XP (32-bit)

qemu-system-i386 -drive file=WinXP.img \
-cdrom WinXPInstall.iso -m 512 -soundhw ac97 \ 
-vga cirrus -net nic,model=rtl8139 -enable-kvm -boot d

qemu-system-i386
calls the program and specifies the i386 system architecture

-drive file=WinXP.img
loads the specified file as a hard drive (ideally, a blank disk image)

-cdrom WinXPInstall.iso loads the specified file (a bootable Windows XP installation CD-ROM) into the CD-ROM drive

-m 512
gives the emulated computer 512 MB of RAM

-soundhw ac97
gives the emulated computer an Intel AC'97 compatible sound card

-vga cirrus
gives the emulated computer a Cirrus Logic video card

-net nic,model=rtl8139
gives the emulated computer a RealTek RTL8139 ethernet adapter

-enable-kvm
allows QEMU to use KVM virtualization, emulated machine will run more efficiently (will likely require admin privileges on the host computer)

-boot d
directs the emulated computer to boot from the CD-ROM drive rather than the hard disk drive for installation; remove or switch to -boot c after successful install