What you must understand is that the "safe experience" that you seek cannot be taken for granted by just installing some anti-malware software such as a antivirus.etc. You can get trouble even if you have all of these.
Follow the guidelines I have suggested in my earlier post. And above all use your commonsense while downloading/installing programs. Do a bit of research on the program before installing it and see what other people are saying.
You may find it funny but briefly read the user agreement before clicking "I agree" in a program setup. Sometimes they tell you that they are going to install Adware and other junk on your system.