It can be done but not recommended since MCE is a little single minded about sharing.

MCE runs a process, "ehrecvr.exe," which monopolises tuner devices on the system, this will prevent any program other than MCE, from using a tuner device resulting in no picture or sound during the "Test " section of the Setup Wizard. The solution is to disable the service responsible for starting the "ehrecvr.exe" process.

1. Navigate to CONTROL PANEL --> ADMINISTRATIVE TOOLS --> SERVICES.  
2. Find the "Media Center Receiver Service" in the list; rIght-click on it and select "Properties."
    
3. On the "...properties" window that appears when you do so, find the "Startup type:" entry on the "General" tab. Set "Startup Type" to "Disabled" (as shown in the screenshot below) and hit APPLY.
4. Reboot the computer.

    You should now be able to use capture software other than MCE.