First game for me, SHenmue 2 is still absolutly amazing, but I keep coming back to the first game more. I prefer the more natural realistic graphics of Shenmue 1 than the bright, sometimes cartoony look of the second. Shenmue 1 uses alot of greys and just feels more realistic to play, I guess because of the slow paced nature of the game also I get this feeling.
Also with Shenmue 1 being much smaller it allowed me to appreciate the detail put into the game more so than Shenmue 2, where you don't take as much in whilst playing and tend to rush a little more through the game than the first. The detail was much more striking in the first game, with the phones you could use and all of the unique dialogue at different stages of the game, and alot of hidden scenes that you don't see each play through.
Shenmue 1 had a bit more gameplay vartiey aswell, what with the vehicles like the motorbike riding, forklift truck racing and working, kitten caring
Both are great, but with Shenmue 1, I love that I know the whole game off by heart, conversations and i'm filling in the sentances outloud before they speak, it's crazy how much dialogue you can remember, whereas I don't really have that connection with the second game, even after completing it like over 10 times.