I'll agree that some of the lines are a little silly and campy, but there are plenty of imaginative lines. If the dialogue was really wooden, it would go something like.....
Leia
Governor Tarkin, I should have known you were behind this. I knew Vader could not be alone.
Needa
Good, I'll notify the command ship right away.
Luke
I'm looking for someone
Yoda
Who are you looking for
Luke
A Jedi Master
Yoda
Oh, you must mean Yoda. I'll take you to him now
Han
Not entirely stable? Chewie can you and Threepio look at the hyperdrive.
Han (instead of don't get excited)
Calm down
Leia
I'm not hyper.
Leia
Would it help if I got you the hydrospanners?
Han
It might
Leia
I don't know where you got that idea Han
Chewie laughs
Han
Stop laughing Chewie. But you didn't see us in the south passage this morning. She expressed her true feelings for me.
Leia
You're lying!
Han
I am not.
Leia
You don't know anything about women
etc