Emerson 7" HD tablet (em749_748) blocking internet in strange ways

I found this tablet a week ago buried in a box while my family was cleaning the house. I was told it was useless and didn't work, but I figured I'd give it a chance before getting rid of it.

At first, I though it was just really slow, but I looked up the specs and it's processor has a higher CPU frequency than my phone. I added videos from my PC and it ran them without issue. The internet seems to be having trouble for some reason, depending on the app/website.

What works: Google chrome Vimeo via Google chrome Most HTTP websites

What doesn't work YouTube app YouTube via Google chrome Google play store Gmail app Just about any app

Even stranger if I connect to my WiFi, use PdaNet to USB tether, give internet access to my PC, I can use YouTube and Steam just fine.

I think I'm down to the bare minimum apps installed, so I don't think it's a virus, unless it came with a virus installed. Still open to the possibility though. Feel free to ask for more info, I'd appreciate the help :)