Monitor Or Graphics Card Or Software?

Well I woke up switched on my PC to find my resolution has dropped on my desktop from 1600x1200 to 1440x900 so I thought "oh that's weird easily fixable though" so i increased the resolution through the control panel only to notice on 1600x1200 theres massive display problems. I will try to explain the best I can.

about 75% away from the left hand side of the start menu going up i get lines on my screen going up and what looks like distorted start menu quick launch icons (im guessing if i was at 1440 res thats where abouts they would be) also the screen is in widescreen like my monitor but its squished and i tried the 1600 res in my games and it cuts the bottom of my screen off.

Heres the kicker I could have swore b4 this morning that my max resolution was 1680x1050 as i think it was a monitor restriction not card the thing is I cannot select that resolution just the 1440x900 and 1600x1200 as my max res. So how can I go back to 1680x1050?? as windows refuses to let me select that resolution as do my games... I'm wondering if it a graphics or monitor prob or something a lot simpler..

I have re-installed the latest nvidia drivers and no change I have noticed however if i switch to the 1600x1200 and restart for about 2 secons when shutting down it switches to 1680x1050. So i'm guessing its software related.

here is my monitor
Advance Tec Ltd Yuraku 22in MABWBA Black Widescreen Res 1680x1054 Multimedia TFT Monitor

well i temp fixed it by unchecking the "hide modes that this monitor cannot display" box in advanced settings is there any better way of doing this though? as i can no longer run my games at 1680x1050 which i could do b4 I just get errors.