Go to the NoScrub's Iris Online folder and go into the Option folder and delete user.opt file and any files with the extension .opc (there shouldn't be any .opc files if you haven't yet created a character). This will reset the client settings to default, including resolution settings.
Now open the IrisLauncher.exe to start the game but do not touch the resolution settings of the launcher - they can sometimes be incorrect for your graphics card so leave them alone and only change resolution from within the game itself.
If that doesn't help you should try reinstalling the client but it's seems unlikely anything is wrong with the client install if it was working for you earlier today. Client data can become corrupted during the patching process but when that happens you would get error messages or the client would refuse to open at all - from what you describe it sounds more like a graphics card issue - It might be a setting you changed on your computer or some other software interfering?
Anyway try what I said above and let me know how you get on. I'm leaving for the evening now but I will be sure to check for a reply when I return in the morning.