DR2 does technically look better. It has better lighting, self-shadowing, better graphical effects, ragdoll (did DR1 have this? don't remember), zombies that can be cut in any direction (like Afro Samurai), etc. But this is all at the cost of framerate, so they still fucked up.
I do think DR1 was the better game though. There's a lot of improvements in DR2, but escorting survivors is simply nowhere near as fun because it's babby easy now. You can pick up a group of survivors, run to the other side of the map, pick up another group, then run straight to the safe room. You don't even need to glance at the survivors that you have in tow because they are never in any danger at all. In DR1, keeping the survivors safe as you dragged them from one end of the map to the other in order to save everybody was way more interesting and fun.
TLDR, they dumbed it down a little too much.