Right.
First, some more information needed;
The discs you received with the Mac were for 10.6.2 - build no. (on the disc) 10C2234?
If so, that would make it a late 2009 model - does that sound right?
If you're not sure, there should be a couple of numbers on the base of the stand, one beginning 'EMC' and another beginning with A and 4 digits. There may also (or instead) be an order no.; something like MB123LL/A.
Tell us as many of those that are there.
All this is to establish that the install discs are the right ones, before we try again.
Assuming they are the right discs, boot from the installer disc again and go to Disk Utility.
This time, select the physical drive (the one with the maker's name and disc size, above the volume).
Run Repair Disk. If that comes up as disk OK, click the partition tab. Select the partiton from the drop-down above the graphic; 1 partiton is all you need. Go to the options button and ensure that the partition scheme is GUID and the file system to Mac OS Extended (Journalled). Name the partiton (usually Macintosh HD), click Apply.
When that's finished, select the new volume in the sidebar (indented to the right below the drive) and go to the Erase tab. Click erase (do not use security options).
When that's completed, close DU and continue with the installation.
Afterthought - which item did you have selected when you did the zero erase? The volume Macintosh HD or the top item which is the physical drive?