I would like to present a basic step-by-step guide to 1)resizing pictures and 2)creating panoramic views. To do this I will look at two programms you can use for this purpose.
The first is Irfanview. In short Irfanview is a picture viewer on steroids and it is free so anyone can use it. You can download it from http://www.irfanview.com.
The second programm I want to present is Adobe Photoshop, very expensive but simply the best graphic editing software out there. With Photoshop everything is a bit more complex compared to Irfanview but on the other hand PS is much more powerfull and offers advanced features (which I am not going to detail ).
Before I start I want to add that my methods are not the only ones and probably not the best but they work and I think are easy enough to comprehend
I also want to note that English is not my native language so feel free to keep any grammar mistakes or typos

Resizing pictures with Irfanview:
1. Open the picture with Irfanview, then use the mouse to make a selection of the miniature (simply press the mouse button and drag a rectangle around the part you want to select, see screenshot below). If your picture is too big to see the whole miniature zoom out a bit. The current zoom factor is displayed at the bottom.
Personally I prefer pictures where just the miniature is shown since this is what the picture is all about. Also you can create smaller pictures sizewise by eliminating unnecessary background.

2. Select Edit->Copy or just press ctrl+c to copy the selection to the clipboard.
3. Select Image->Create new (empty) image to create a blank image. Just click OK in the pop up dialogue (alternatively you can open a new instance of Irfanview without a picture to display).
4. Select Edit->Paste or press ctrl+v and the selection will be copied into the blank picture.
5. Now that we have only the miniature it is time for the actual resizing. Select Image->Resize/Resample or press ctrl+r. In the pop up dialogue enter the new height of the picture. Make sure that 'preserve aspect ratio' is checked, otherwise your picture will be distorted. The new height will then automatically be recalculated. Press OK and your picture is ready. Select File->Save As and save as .jpg. The default settings for compression are ok and usable.


IMPORTANT: When resizing pictures make sure to never enlarge them. Enlarging pictures makes them blurry. Reducing pictures in size is never a problem since no sharpness is lost but do not enlarge or risk loosing sharpness.