I'm new to KVM. I use the following way to create and start a guest KVM machine.
qemu-img create -f raw centos.img 100G
/usr/libexec/qemu-kvm -hda ./centos.img -cdrom /usr/local/CentOS_5.6_Final.iso -m 1024 -smp 1 -boot d
/usr/libexec/qemu-kvm -hda ./centos.img -m 1024 -smp 1 -boot c
When the login page appears, everything seems right.

When I log into the system, it show me like this. Note the following image shows what I saw when I just log into the system, without move my mouse or press a key.

Take a closer look.

When I click the left mouse button, it shows me this menu.

Anyone can help me with my problem? How to fix the graphics in the guest machine?
Thanks in advance.