If they don’t like Gershwin, it may or may not be a lost cause.

And also like Paul said, remixes of classics are mostly trash. If anything, they might be more likely to make your friend feel something along the lines of "See, this is why I don’t like classical, if you don’t put a catchy beat behind it, it’s boring!"

There is always the chance that a particular individual may just be predisposed to never liking classical, or any particular type of music, but if you want other ideas:

2. I’m also in agreement with Suhwahaksaeng in that your friend may very well have enjoyed classical music without realizing it.

3. It may be helpful to make sure your friend understands that not all ‘classical’ music is alike, and that Classical music is in fact just one of many eras of what is sometimes described as "western art music" for lack of a better term. Personally, between the Baroque, Classical, Romantic, Impressionistic, 20th Century, etc, eras, Classical is one of my personal least favorites in general.

Of course, Beethoven was brilliant. His 5th Symphony, or at least its main motif (da da da DAH!) is one of the most universally recognized 4 notes of music globally. He helped influence the evolution from Classical to Romantic, I believe.

But enough digression,

4) I don’t know what kind of music your friend likes, but you might consider playing him the first movement of Vivaldi’s Winter, really loud, out of kickin’ speakers.
That and some Bach.

I don’t know what your classical preferences are. Personally, although I grew up on virtually nothing but classical in the general sense (piano studies) and video game music (I liked my video games, and I like music, what can I say), I personally am not one of those people that holds classical music in general to be elite compared to modern music in general.
What I mean to say is, looking back at, for example, the sonata allegro form, very much of classical music is just as formulaic as much music is today.
What really separates things, for me, is based on an individual piece-to-piece basis. I’m a huge fan of Ottorino Respighi’s Pines of Rome, however, it may be too much on the dissonant and odd side for your friend, though conversely, it may be exactly what he needs to hear to be converted.

I will end, having said admittedly far too much for my first answer on this site, with simply repeating:
Try what you will, and good luck, but success may not be guaranteed.
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Find out what their favorite song is that has a beat to it and find it redone in orchestral instruments and just listen to it in a car ride and don’t even mention it. Just see how long it takes them to pick it up and I almost guarantee they will be interested after that.
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While you’re at it, look into Brahms, Tchaikovsky, Wagner, Ravel, Copland, and Gershwin.

And please, PLEASE, avoid those classical remixes; they’re all junk.
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