Drops offline

Hi my 2*3GHz dual core bought from ebay keeps dropping offline, It also defaults to working offline mode when booting up.It also never remembers passwords even though i clicked all the right boxes in preferences.It came with Leopard 10.5.6 which i upgraded to 10.5.8 so i could install logic pro9.Logic 9seems to function fine .I also downloaded firefox 3.5.6 but the same thing happens even in Safari.The page rebuilding seems a bit sluggish when i click on the hard drive to look at apps ect.
I'm not to up on computers just the music programs.So i ran disk Utilities ,verify disc permissions and found lots of system has been modified and cannot be repaired ect.See image..What do you think? I dont have the osx install discs as this was a refurb from ebay..

Hi Steve,

Every Mac (even from ebay) should come with the original Install Discs...

I would only recommend doing a complete erase of the Mac and then reinstalling Leopard. Hope you have a copy of Leopard???

Another thing, which would require the original install discs, would be to do a hardware diagnostics test... to check Airport Card and other hardware.

I'd suggest booking a Genius session and popping to your nearest Apple store to get it checked out, and contacting the ebay seller to see if you can get the install discs.

Best
Rounik