One of the most common problems with applications downloaded form the Internet is the risk of viruses, spyware or trojans. These applications can be included inside any application. In some cases, these applets are not added maliciously, but in any event they are to be avoided because you do not want any application installing unwanted software. I recently was perusing the Internet and ran across a great application that can help solve the problem of applications that install these undesired software packages.
The software is called Sandboxie and what it does is create a virtual environment for you to install an application that you are uncertain of. It sits between the application and the OS and prevents any of these undesirable applications to write to your system. The beauty of it is that you can run the downloaded application in Sandboxie and it will operate normally and will think that it is has installed its undesirable payload, and Sandboxie will prevent any permanent changes to your OS. You can selectively run Sandboxie on only certain applications which can provide a tremendous piece of mind.
I have not tried this application yet, but it looks compelling. Best of all, it is free! Definitely check it out. I plan on installing it in the next couple of days.