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You are reviewing the correct options and it is up to you to determine which option should be chosen for any given page. If you have relevant or similar content on another page, the best option is to perform a 301 redirect to that page. For example if you have a page on "Christmas Deals" then in January you may wish to 301 redirect to your "After Christmas Deals" page. There is a strong likelihood that anyone who was interested in Christmas Deals would be interested in the new page. On the other hand, if you have a page on a specific topic which is no longer active and there is not another relevant page on your site, offer a 410 response code. This will allow search engines to update their records a bit faster. If you let the page 404, then the search engine will not be sure if the content is temporarily unavailable or not so your listing will be kept for longer. With either of the last approaches be sure your 404/410 page is helpful. It should contain your site's normal navigation along with a search function. Don't dump people on a page where they need to press the Back button on their browser.

It seems to me you're a bit confused between canonical URLs and URLs that have been rewritten. What a canonical URL does is telling the search engines what version of your URL is that canonical one, which can for example exclude some parameters. One the actual url www.example.org/special/?foo=bar&test=3 you can tell the search engines that www.example.org/special/ is your URL (and therefor the parameters foo and test will be ignored and won't create any duplicate content). But, these canonical URLs have to exist! To create new URLs, you should either look if the CMS (Content Management System) you're using has the option to switch on static URLs (sometimes called SEF URLs). If you're using a custom system, or your CMS doesn't support static URLs, you can search google for terms such as: mod_rewrite, static urls php, htaccess url rewrite.