Temporary Solution

Seems restarting the system helps refresh the glitch with W, Tab, and Window Button. This tells me it's a software issue and not a hardware issue, thankfully! Using a laptop, so can't really replace a keyboard. I'll have to do a restart every now and then if it shows sign of getting worse just to refresh it.

Just glad it's a software thing. I did a anti-virus and anti-malware scan (samething I suppose, but wouldn't hurt to do both types) and nothing was picked up. Don't know if there is any virus or anything that would cause keys to not respond well, but had to be sure nonetheless. There must be something clogging up the command input or preventing it to reach the system to make an output or a response to it. I don't know and not sure how to check either.

For now gonna avoid FPS, Multi/Online, and any games that will only respond to WASD for a bit. Will have to avoid the TF2 server when it's on a competitive/objective map too. I wouldn't mind if it was just Tab and Window, but with W... it'll limit myself. I could change my key binds but will have to figure out to what exactly on some games, if at all possible anyway, and able to adapted to the new change too.

Update: Sigh... nevermind. They have already become barely responsive just minutes after the restart. However after closing a game like TF2 or minecraft, becomes more responsive again... really a software issue, just not sure WHAT exactly. Nonetheless, this is so... upsetting to me.