The CTRL ALT DEL doesn't work: 

To make the CTRL ALT DEL command to work, run the VNC server (Tight VNC or UltraVNC) as a service (so not in application mode), and allow the CTRL ALT DEL feature in your system: Tutorial here 

The remote view screen is completely black 

Disable the hardware acceleration from the application settings. For example, If you are using 2 monitors on your computer, the generated bitmap is too much large for the hardware acceleration. Also, on some devices, bitmap size must be a power of two, that does not match PC screen size. 

By default the second monitor is not captured by UltraVNC. 

You can activate it by editing the ultravnc.ini file (http://www.uvnc.com/docs/uvnc-server.html) 

Keys to change in the file: 

primary=1 

secondary=1 

When using multi-monitors ( driver required) you can define the default behavior. Show only primary/secondary or both