Everybody wants to be Notch, but nobody wants to write code for years on end.
If you actually have the free time, and the ability, to pursue at least one of your ideas then I think the only way you can answer this question is to force yourself to see one through to the end. I'm kind of the same way - tons of old Game Maker projects that got abandoned because I wasn't capable of executing on the ideas I had, things got too complex or I just stopped being interested in them once I solved what I thought were the interesting problems.
Since i'm taking programming classes now, I've decided to finish one ridiculously simple game (Space Invaders) just to earn the basic mechanics of 2d game design, in C++. Of course now you have Game Maker, Unity, Unreal and various other frameworks to choose from, but my personal interests are a bit lower level. I started in January and haven't finished yet. Just the basics are turning out to be much more complicated than I would have anticipated, and I haven't even bothered with art, sound, or gameplay that's anything beyond the rudamentary. I spent weeks building (from scratch twice) a basic entity/component system to work with SDL, not because I had to, or because that was the most efficient way to build the product, or even because there weren't existing libraries for that, but because that's the problem I was interested in solving. So something that would probably be a weekend hack for a better programmer is turning out to take the better part of a year, because I'm more into the journey right now than the destination.
Having 'vague ideas' doesn't really give you a good sense of the scope of what those ideas might actually represent. I would second the other comments here suggesting you find a simple game and try to clone it, but I would also decide whether what you're interested in is the coding of games, or the authoring of games. In other words, would you feel more satisfied writing C and C++ code, or working through a framework like Unity or Game Maker? Because the latter would probably be faster for just prototyping or getting a feel for an idea, and almost certainly better for making salable games if you're not already a professional low-level game programmer. But personally, I think the former is more fun.
Pick a language, pick a framework, pick a game, accept that the results won't be perfect, and just go for it. That's the only way you'll discover what your passion actually is, or isn't. If you can't commit to that then, yeah, you're probably not going to commit to something real. Which is fine. Plenty of people want to be writers too, who never write. People like that tend to spend a lot of time taking writing classes or hanging out on writing forums and in writing groups, because 'being' for them is more interesting (and easier) than 'doing'. It's not an uncommon phenomeneon.