Lemme guess, those that acted very arrogant toward your post (and directly you) about only about a years experience and aspiring to play very difficult pieces are probably justifying their own experiences and lessons as children and how they sat through hours upon hours of lessons for 4 or 5 years and only came away with Chopsticks and Happy Birthday and want you to go through that as well. And a couple of ABRSM exams to gloat!
Ha!
I just described my older sister and how she acted toward me when she heard me attempt the 3rd movement of the Moonlight sonata in the early days of my pianistic youth.
But when she heard me play the first and second movement at other times, the look on her face... She didn't say anything (at least not after she told me what those markings I didn't understand were: naturals, flats, and sharps). Yes, my theory was severely lacking in the beginning. The point was, when she
heard me (play those right notes), she couldn't say anything. I can remember that look the first time. Perhaps jealousy? Even a bit of inferiority? She
never played with such expression.
She was never the musician. Just the pianist.
I was always the artist, and found a new mode of expression.
She doesn't say anything anymore.

(<--- should be a smirk). She may have a larger technique base but she doesn't have much of a musical base. And now let me gloat: I rule!

See, those pieces that you have already learned were some of my beginning repetory. I'll admit that in the beginning, I thought that to play the piano, all I had to do was hit the right notes at the right time. Experience has shown me it's not about that hitting the notes at the right time but the music (though hitting the right notes at the right time really helps almost all the time, hehe). But after this early phase, I became solely focused on the
music that I was able to create. It was the music, not what was written on the pieces of paper, that guided
how I played. Though my piano teacher disagrees heavily on this criticising my technique but worse, my expression! :-/ (By the way, I don't pay attention when she tries to show me expression. I've heard my sister play.

) But I agree with her when she criticism my technique.
But then you asked if it were possible to play la campanella, HR2, et Rach 2. Clearly, you've actually listened to piano music! Most children never hear another piano making noise until they are much older and their favourite advanced tunes just so happen to be Chopsticks and Happy Birthday. My god! Just look at his virtuosic Chopsticks! I've never heard Chopsticks played so well before! MY GOD! We have a Liszt in the making!
Point is this: most children never hear another person play on the piano what we consider advanced repetory. They, after 3 or 4 years, are still learning from Children's Books (you know, with the pretty pictures on each page!) What they aspire to be as a pianist never comes from these picture books. Until they grow up and are self-sufficient enough to explore on their own... the cow-dung load of piano music they find and they think, I want to be able to play that.
Why do they want to play that? Is it because they get to move their fingers really fast and all over the place? No. It's because the pieces you've mentioned are musically complex and most importantly, beautiful. Who doesn't want to play beautiful music? The unfortunate side to complex and beautiful music is that it is often the most difficult to play. And so the musicality of these pieces are often set aside in favor to focus on the technicallity of them. These are technically difficult pieces but not impossible to play assuming you have the minimum requirements: 10 fingers, 5 on each hand, and are capable of sufficient reach; the ability to hear; and a well-operating piano.
One point I want to make explicit:
Music is not difficult to make. It is the constraints of the mode of making that music which causes difficulties.
Now as for the time constraint you have set yourself, to learn one or so of these pieces in under two years, can you do it? With proper guidance, the answer is yes. Without that guidance, the answer is still yes though there will be a lot more trial and error and even though you are able to play the notes at roughly the appropriate time, you may be lacking in the most effective technique for the purpose of making it sound the way you want it. This goes the same if you had proper guidance but perhaps to a lesser degree.
Last thoughts:
This thread is motivating me to learn La Campanella, and the Rach 2. I don't care much for the Hungarian Rhapsody, though (his rhapsodies aren't musically very interesting in my opinion, but darn fun to play!)
You could prove these virtuoso Chopstickers wrong and learn these pieces and play them well within your time constraints but that wouldn't be the most effective goal in the long run. So aim to learn how to make music, then turn to them and say... "just have a listen."
Lawrence
