You may not be aware of this, but VirusTotal saves the files that you upload. Businesses that have a subscription to VirusTotal can download those files you uploaded, it's part of the terms of service. I wouldn't upload anything potentially sensitive that you don't want the entire world seeing.
While VirusTotal is indeed a useful service, I don't see it being beneficial to scan everything you encounter. Assuming you're running Windows, any of the big players in the AntiVirus game such as Windows Defender, should be sufficient most of the time.
Is there a reason you're worried about this game installer? Is it from a legitimate source, or is it something you grabbed off a P2P service? Things such as games which unpack giant executables aren't as likely to be caught by AntiVirus. There's a lot more space to hide something malicious that seems innocuous.
For something that size, I would recommend running in a sandbox. Cuckoo will analyze files and executables dynamically. Sandboxie doesn't analyze files, but rather provides isolation, so if a program is malicious they won't be able to touch the rest of the computer.