Some windows don't display fully.

I had acquired an eMac awhile ago that was going into a kernel panic at bootup. Nothing I read or researched seemed to do the trick. Recently as I was walking through a local Goodwill I found another eMac (with what appears to be a few BB divets in the display) for $10 so I purchased it. This eMac was an older 700mhz version that was running OSX 10.4.2 and booted just fine. There were a few permissions issues, but I think I've resolved them. So I then booted the non-working eMac into firewire mode and did a disc wipe/clone from the working system. Now the previous kernel panic is gone, and the system boots and allows me to log in, but the display is not using the full capacity. If I go into the Display properties the window never fully fills out (like it does on the other eMac) and I can't change the screen resolution.

I've attached a couple photo's below but it's a little hard to see for sure other than you can tell that it isn't using the full capacity of the display. The Display properties window is lacking a few tabs at the top, and also the minimize, maximize, close buttons in the top right of the window. I've noticed this on a few other windows that I've looked at on this system.

I hope I haven't rambled and completely confusted the issue. I have no OSX discs so reinstalling is pretty difficult. Is there some tool I can use to reset things? Is there a way to get copies of the OSX discs? As I've mentioned before I'm trying to immerse myself into the Mac culture and start learning to navigate in it. I'm not quite able to drop the cash required to buy a new system and I'd like to keep messing with these as I think I will learn a lot more by solving these problems than by just having a nice shiny new Apple product to play with.

Thanks in advance! One thing I have noticed is that this Apple support community is awesome! Just hoping someone has an answer that with any luck doesn't include "get some OSX discs" because they seem pretty scarce to me.

Greg