Since I went over to HDMI the display on my desktop is too big; I cannot see the start button or any of the left-hand column of icons. How can I shrink it back to "normal" size please?

That should be controlled in Screen Resolution and is strictly controlled by your video driver. If you do a Right Click on the Desktop you should have Screen Resolution as one of the options.Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Click Start on your desktop... click Control Panel... click Display... click Appearance... change font size at bottom of box... click apply Hope this works!!!Windows 7

If you've got any "Auto Adjust" button on your screen or somewhere in your screen's menu, try that first than you can try what Rick and Deitzzz suggested. ThanksKubilay Elmas