URLMon.dll is a file used by Windows to help embed a series of objects into various software applications on your system. The likes of Microsoft Word (which allows you to embed HyperLinks & WordArt), as well as other programs will use this file to continually help embed a large number of different objects into your computer. Although this file normally works well, the problem it faces is that it's continually causing a huge number of problems for your system, resulting in the errors you're seeing on screen. To resolve this problem, it's recommended you use the steps outlined on this page.
The way to stop this error is to first place a fresh copy of urlmon.dll onto your PC. This can be done by first downloading a new copy of the file from the Internet (there are a lot of websites which provide access to free replacement DLL files now), and then replace the file you currently have on your system, in the C:/Windows/System32 folder. This should be pretty easy to do, if you make sure that you're able to re-register the file when you replace it on your PC. If this does not work, you then may wish to perform a "system restore" to make sure your computer is restored to the settings it had when it was new.
After you've downloaded a replacement urlmon.dll file, you should also look to use a "registry cleaner" program to scan through your system and fix any of the damaged / corrupted settings that may be causing a problem for you. Registry cleaners are popular types of software which work to fix a large number of different errors on the typical Windows PC by scanning & fixing a part of your system called the "registry". The registry is a directory with all the settings for your system and files inside.
You should clean out the damaged database by using a "registry cleaner" program that you can download from the Internet.