So, Click on the icon in the task bar, and shut it down, if you can!
If can't from there, you may have to shut it down in services. Have fun with that (let me know if you need help with that)!
After you have shut it down, the press [windows key], and type "uninstall".
Click on <programs and features>. Select the program you wish to uninstall from there. If it errors out, good luck. Then you may have to go back to a time, and recover from a period before the complete installation! After you recover, run all updates before you go and install the new version.
I would be cautionary about the new one as you saw what it takes to get the old version out, with it looks like no support from the makers of the software!