With a digital camera you should always choose the highest resolution when taking your pictures. Usually, they can't be repeated when they don't work out with a lower resolution. Wings Vioso RX has no problem with large image files; it creates smaller display data for presentation. Larger pictures have much more in store for a high presentation quality.
Slides and negatives should also be scanned at a high resolution. Scanning and editing means a lot of work, so you should do it the best possible way which allows universal usage of the pictures at a later time, e.g. for prints or camera movements with only one section of the picture being visible.
Further information on this topic:
Minimum picture sizes depending on the application