I'm having PC problems again. It's been a while since I last posted, and the help I received was great!

My Gateway PC tower is about 5 years old. About two years ago, I decided to upgrade my monitor and buy a Gateway Flat Screen/Panel monitor. It's been working great until now. I don't know if it's my monitor, or my actual computer.
About a few weeks ago I booted up my computer and noticed the resolution wasn't all there. The best way I can really describe it, it looks like the computer is in 'Safe Mode', but I assure you it's not. It just has that 'Safe Mode' resolution, or another way to describe it, is it looks like the resolution from a really old CRT monitor. I don't know if my monitor is going out or if it's my actual computer. The monitor is only two years old. I read on the internet somewhere that it could be something with the video card. Is that possible?
Any help or information would be greatly appreciated.
Thanks!
UPDATE:
I attached a picture below. It's a picture of the smilies when I was making the post. I don't know if this is of help or not. I also noticed when I was restarting my computer because of a windows update. The resolution kept jumping back to normal to what it is now back and forth, until it finally stayed back to problematic. So now i'm thinking it might not be the monitor.
