The pics will stretch if the aspect ratio of the new monitor is different than the old one. That LG monitor has a 16:9 aspect ratio, which is gradually becoming the standard for monitors and tvs. All the old monitors (and tvs) had 4:3 aspect ratios. When you switch to a "widescreen" LCD monitor from a 4:3 aspect ration monitor you'll also need to switch screen resolution to make it look right.
All these LCD monitors will look best when screen resolution is set to the native resolution of the monitor. For a 4:3 15" it's usually 1024x768, for a 17" usually 1280x1024, for 19" usually 1600x1200, etc. If you aren't sure which resolution is native try changing them around ... one of them will be clearly more sharp and look better than the others and nothing will be stretched.
Eric
