Obviously some things are screwed up in your system. The safest thing to do would be to back up any data you don't want to lose and restore your computer to factory settings. Of course if you had recent full system backups, you could just restore from one of them, but I'm assuming you don't have any of those.
When you've gotten your system back like you want it, I urge you to get yourself an external hard drive and a good 3rd party backup program. You can set it up to do everything automagically at the time and frequency of your choice. 1 TB external hard drives are about $70 these days and a really good FREE backup program is the Easeus todo backup free which you can download from
http://www.todo-backup.com/products/home/free-backup-software.htm . That can save you a lot of time and frustration the next time something like this happens. Sooner or later it happens to all computers for one reason or another.
Good luck.
I'm dumb, I know...I hit my PC tower and the screen froze. No sound or nothing. I turned it off and on and a screen came up asking me about installing drivers. I chose the option along the lines of "Na just go continue" since I already have everything installed. Now things have changed.
1. When loading drivers and stuff at the black screen at the start (where you'd enter BIOS) it says "loading ASUS express way" and loads fine. But it never done this before. I disabled the message in BIOS but that hasn't solved any problems.
2. When I load to desktop, nVidia pops up and says "nVidia com object has stopped working". Closing it does nothing and attemp to fix before closing does nothing.
3. When I'm on Firefox it tells me every website is unsafe and I need to do the "I understand the risks" and add an exception for every site.
4. I can't load Steam. It says something about the program being in use by something else or something like that (I've forgotten and I'm in bed now but I can clarify tomorrow).
How screwed am I? 
I run windows 7 ultimate 64-bit.
NVidia GTX 250
8GB DDR2 RAM
Quad core processor (I can't remember which but again, I can check tomorrow).
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