Steps to add qxl driver on windows 7 enterprise 32 bit virtual machine:
1) Add following in VM config xml file.
<video>
<model type='qxl' vram='8192' heads='1'>
<acceleration accel3d='yes' accel2d='yes'/>
</model>
</video>
2) Start virtual machine.
3) Open elevated command prompt
4) bcdedit.exe -set loadoptions DDISABLE_INTEGRITY_CHECKS
5) bcdedit.exe -set TESTSIGNING ON
6) download qxl installer from http://spice-space.org/download/windows/spice-guest-tools/spice-guest-tools-0.59.exe inside virtual machine.
7) Run the downloaded installer.
8) Reboot the VM.
9) check to see that the video hardware is set to qxl
Note: Step 4 doesn't work in service pack 1(64 bit). Alternately you can press F8 on boot and disable Signed code checks.