Choose a TV or monitor with a wide range of control over these adjustments, and preferably one where they can be made via a remote controller rather than on the set. More variation than can be got from controls on the set itself can be had via Audio-Visual control units of the sort used by amateur video enthusiasts. You should ensure that your TV or monitor will accept signals from your chosen AV controller. Resolution TV resolutions are fixed by broadcast authorities. Ignoring High Definition and widescreen TV, the standard is 625 vertical lines of information in the UK, some of which are not displayed.
Some tubes are crisper than others, but the basic limitation lies in the transmitted image.
In contrast, computer monitors come in a wide range of resolutions. If your intention is to show video within multimedia, you have more choices to make. Go for high resolutions if you can, even on small monitors. You will have better setup options. For instance, you will be able to display fonts with better curvature, less obviously pixellated under high LVA magnification.