SOS. Database Lost

Hi All: I'm From Spain and I'll try to write in english as best as
possible:

I'm new in the list, and I have a serious problem: I am novice with
Postgresql and I haven't found any solution.
I Wil descrive the scenario:

I have Postgresql 8.0.1 running on Windows 2003 Server.
I have a Backup of my database, but is a little old

And here is my problem:

First, the Postgresql service didn't started (really started, but shut down
immediatly)
then I copied all the "postgresql" folder in other place, uninstalled and
reinstalled Postgresql, and then overwrite the "data" folder with the one
from the copy that I did.

Now, the service starts properly, but the database doesn´t work. I did
"pg_resetxlog" (I don´t know what it does, but I saw it somewhere).

From pgAdmin III, I see the database, I access it, I see the tables and
their properties, but no data. I get the error "xlog flush request
6D/432AAAA8 is not satisfied --- flushed only to 0/C03D020 CONTEXT: writing
block 925 of relation 16631/17254/18128" when I try to view the tables

I would need to know if I can recover the data from the tables and how to do
it.
I thank any suggestion that can help.

Luis Perruca