Haha, I see your name pop up once every few months. Since you're not a regular here, I really wonder what made you pick this forum to ask your question when there are so many more suitable forums for this particular topic.
But anyway, making you're you're safe with executables is simply a matter of common sense + antivirus.
1. Is it from a trusted source, such as a downloaded installer from Adobe or Google or your favourite local news website, then it's most likely safe.
2. If you scan it with your virus scanner and it comes up with no threat, it's likely safe.
3. There's a number of free services that check your executables for viruses such as Malwarebytes or https://www.virustotal.com/
What it boils down to is: avoid very shady sources and if you're unsure, make sure you scan it with your virus scanner before you open it. Common sense when downloading goes a very long way in avoiding trouble.