You are most likely not entering the correct database information.
What did you enter as your vbgallery table prefix?
For instance the vbgallery table prefix is ppgal_
Now if your vb has a table prefix say of vb_ then your vbgallery table prefix you enter would be vb_ppgal_
As long as you enter the correct database info and server paths things would should operate fine.
I can look at your config file and determine if your stuff is right if you want.