If you want to make a really nice looking game in using SDL or OpenGL, then yes, even if it's just you, it is possible. The problem is, if this is your first game and you plan to make a kickass MMORPG with stunning 2D graphics, you simply aren't going to be able to do it.

You need to start out small. It's really as simple as that. 99% of game indie game developers are not going to produce a big title that generates large amounts of revenue, for their FIRST game. Even if your goal isn't to generate revenue, writing a full-scale, beautiful, stunning 2D game, MOST LIKELY won't be realistic for you if you're just starting out. I really would start small, tower defense games, pac-man clones, pong-like games, etc. are all great places to start. And you need to get more than just the basics of what you need all down before you try to develop the full-scale 2D game of your dreams.

That being said, ALL of the really nice and successful 2D games out there are successful because of great game ideas, great game physics, collision detect, etc, AND stunning art. If you are not confident in doing all of that yourself, what you're asking most likely won't happen.

and maybe I just can't find any good one but everytime I try to look for projectsmade in sdl, sfml, opengl and directx they all look horrible and boring.

OpenGL and DirectX are the industry-standard low-level graphics APIs for PC development. I would expect every 3D game in the last decade (just to limit scope) that people played on a PC used OpenGL or DirectX. Every game on the XBox uses DirectX. What you're probably finding are hobbyist projects or tech demos designed to play around with or showcase a particular feature of these libraries. And like shadowgamesco mentioned: it takes really good ART to make a really pretty game (most of the time). Chances are any hobby project you find done by a singular programmer probably doesn't have any good art to use. It's uncommon to be both a good programmer AND a good artist.

I wanted to know if it is possible for a single person to make a game in sdl and or opengl and with this i mean a big game not just a pong or something like that. Should i use a game engine instead?? I want to make a nice looking game, i prefer 2d but i dont dislike 3d. I also like to code so I wouldn't like to use one of those engines where you don't code at all.
I feel that even though engines help a lot they also limit what you can do and also even though I like the flexibility that using sdl and opengl gives you but it seems to hard and maybe I just can't find any good one but everytime I try to look for projectsmade in sdl, sfml, opengl and directx they all look horrible and boring.

First - yes, it is possible. But it is hard work - a bit easier if you use engine, but still huge amount of work.
I think that if you want to make big game then creating art will become bigger task than code. Of course it depends on the kind of game you are building - if you are clever, you can create very rich environments from simple elements - like Minecraft. But in any case you need high-quality art for nice looking game. If you are not modeler/pixel artist/background artist then learning to create it will take very long time.

I know I must start small but I want to learn something that allows me , when i have the knowledge, to create a beautiful 2d game. So that being said what I would like to make (not know of course, im talking future here) would be something like wizorb , cave story plus or 30 second hero in terms of graphics.

As others have allready said, Graphics is pretty much all about the artwork, if you have a whole bunch of great artists you can make a big and good looking game, if you got one or two great artists you can make a small good looking game, if you don't have any good artists well, you'd better be a good artist yourself.

High quality art doesn't just magically appear from the hands of a skilled artist, it also takes alot of time and effort to create, once you throw in animations it can become incredibly timeconsuming. a few weeks for a high quality, well animated 3D model is not unreasonable. (2D art can be even more timeconsuming when its animated), if you have a small team it is usually a good idea to stick with simpler artwork to get it all done in a reasonable amount of time. (Consistency is very important)

I like the flexibility that using sdl and opengl gives you but it seems to hard

Game development is even harder.

I know I must start small but I want to learn something that allows me , when i have the knowledge, to create a beautiful 2d game.

Well, it's not just a technology issue, as Lauris Kaplinski pointed out. However, from the technology perspective: There is really no platform that can save you from the continuous learning requirement. In other words, if you're trying to find a technology that will enable you to develop any kind of game in the future, without having to learn anything else, you're wasting your time.

And not necessarily because this technology doesn't exist, but more because this "avoid extra learning" mentality is characteristic of those who are fundamentally incapable of developing a quality game.

So, my advice: If you really want to make games, you need to accept the fact that there are no shortcuts, and just start somewhere. Learn multiple languages, multiple tools, multiple engines, and a few years from now, you'll probably have the ability to produce a game of significant quality.

Yes, it is possible. Take a look at my project here: Chesster
It's just me and another dev (handling the art) and I am doing this with SFML. The music is outsourced.
Recently we have completed one year working on this project but we keep going. We have a few more months and our game will be finished!
I guess if you start a project that you are aware of the scope and the tasks you will have to handle as a programmer, then it's pretty much feasible as long as you keep your focus and don't give up because a new better idea came up. Also, it's important to team up with people as dedicated as you, or you might see everyone abandon the boat.
Projects that look horrible are probably just suffering from "programmer's art"!