Home -
Heard the intro on a DBZ movie, and was blown away. Then a friend introduced me to DT by showing me "Home" and I was amazed to find it was the same song. I was astonished by how equally awesome the rest of the song was. I thought it was one of the best songs I had ever heard, and I still do till this day.
The Mirror -
When I was first getting into DT, Metallica was my favorite band (they got me into music) so this song naturally pleased me big time. But it wasn't just the palm-muting riff that got me, it was that keyboard section towards the end of the intro that really got me hooked. The rest of the song followed.
A Change of Seasons -
This song was unlike anything I had ever heard. Listening to it was literally like embarking on a musical, dream-like, journey. I would play this song a lot before I went to bed, and just listen to it as I would lay there. It took me many listens to actually get past the fist 10 minutes though
I always got put off by the instrumental section after the first two verse sections. I wasn't used to 20 minute songs at this point.
The Glass Prison -
I was on blabbermouth one day and I stumbled upon the "RUN!" section of The Glass Prison as played by DT during Gigantour. I thought it was some of the heaviest and most powerful music I had ever heard. Up until this point, I only listened to the above songs by DT and a few off Elements of Persuasion, as I wasn't really interested with the rest of their catalog. TGP inspired me to give the band another chance, and after getting their entire discography... well, the rest is history.