I like shippuuden more
1) I was waiting for Naruto to grow up not to mention he looks soo much hotter, and everyone looks better
2) He grows in mathurity and strnegth. SO many new jutsu, controlling the nine tails, sage mode...and of course sasuke ms, ems, kirin, sakura and her medical ninjutsu, the diamond thing..ect.
3) We learn about what happened to Naruto's parent, who they are and they epic and sad story! I cried when kushina was telling naruto her wishes for him
4) The plot got serious, it is nearing the end, which means an epic climax and resolution. The story got better, more serious and dangerous...it's exciting.
But in all seriousness i loved part 1, the chunin exam arc was great i love that kind of fighting while people get to watch i just wish there was more team 7 epicness during.
I was happy when sasuke made his decision to leave, i love team 7 but sasuke after the battle with zabuza was acting really annoying he was getting on my nerves. Then when he leaves i was sad, but the sasuke rescue arc dragged way too long...then in shippuuden it continued to drag sasuke doesn't need to be rescued he went willingly naruto and sakura never got that. I like an eviler sasuke because i understand he wanted to get revenge and avenge his clan from itachi. After that is got weird and sasuke went crazy..he still is but i kind of like it more/ but i want a real team 7 reunion so i'm so so.
Overall I like shippuuden more because it has more of the things i like..but only a bit more.