If the RAM is compatible with your system, no. There's no way to install incompatible RAM without desperately forcing it, so you'll know right away if you're doing something wrong.
there is no harm in it
No, WolfQuest 2.5 will not do any harm to your computer.
No. Any spills/food can harm the computer.
Depends on the scanner. Normally i would stay away from these
don't download any software that can harm your computer.
No. The Team Fortress Two Mann Co. Store will not do any harm to your computer, nor will any Valve products.
No. Google Chrome will not harm your computer nor install any type of spyware or virus.
You would find any and all information stored in their computer, depending on how good a hacker you are.
No, it cannot.
A harmless computer virus is really, just a virus that can not do any harm to your computer. It cannot access any files in your computer an cannot activate anything. All it really does is just sit there.
no!
It depends. If the software you we're updating is from a trusted site. Then it is safe to update your software/computer.