It sounds to me like you're serious about getting into programming, so let's take it a piece at a time. Yes, you can often achieve same or similar results with different languages, but more often than not, it has to do with which language you know that best suits the job. While I
could write a fairly simple page with a simple database backend in C#, I would personally choose something more like PHP or Python to do the job just because I feel I could reach my goal faster. Someone else may not feel the same way, of course, but that stresses the point - you don't want a hammer to be the only tool in your bag. Learning several languages as you tackle various types of projects is key to building a versatile skillset.
As for your particular project, my first piece of advice is to start small! You need to learn your way around a language, so break your overall goal down into more manageable steps. Start by making a website with tasks - make one page where you put in tasks with date and time, and another page that shows you your outstanding task list and allows you to check them off as you complete them. Then make a third page that shows you what tasks you've already completed. Once you've mastered that, you can move on to integrating some of your other features and tidying up the UI.
Speaking of UI, that brings up another point: focus on functionality first. As you start learning and filling out your page, don't worry about if it's 'pretty' to start. If you have the best looking page I've ever seen as a visitor, but it doesn't do a thing as it should, I won't stay very long before I go find another page that works. For starters, keep a simple white page with some basic form elements to build your task list stuff. Once it works, you can worry about making it look more appealing. CSS, proper web design techniques, and cross-browser compatibility are all essential to good pages, but every one is a topic in and of itself that you will need to study and learn down the road.
Third piece of advice: use languages with wide support as you start your journey to becoming a programmer. The more literature available online, the easier it will be to find help when you need it. For a project of this size and functionality, I recommend using PHP or Python. For a database, use MySQL. Avoid Access - you'll learn why sooner or later, but for now just know that it's not the preferable tool for the job. There are several good tutorials on working with MySQL databases with either language choice (PHP
here, Python
here). We have tutorials here on Ozzu that member have put together for people just like you who want to learn more. There's a good 3-part "Learning PHP" tutorial amongst others
here and a few Python tutorials, including an introduction to the language,
here. If you need even more primers on getting started with one of the two, then try Google searches like
this or
this.
Last piece of advice: Research and ask questions! With so many tutorials and snippets out there, it's tempting to just copy/paste some code chunks together in hopes that they'll do what you intend for them to, but if you really are serious about this then you should read and work all the way through tutorials and try to fully understand the code that you're using and how it works. If something doesn't make sense, then Google it (sense a trend there? Search engines are a programmer's friend!) or ask people who would most likely won't just know the answer, but might be able to explain it to you in a way that makes more sense (like us!).
Good luck!
I'd love to change the world, but they won't give me the source code.