You should have no problem with 4. I have a weaker cpu, 4 gigs of ram and a GeForce 8800 and can run 4 with no problem (and 5 with slight stuttering). I believe Linux is supposed to run Eve a little slower, but I don't think the difference is substantial and your computer outclasses mine enough that I'm 99% sure you'll have no problem.

I believe you can resize the window with EveLauncher though that requires different installs for EVE for each account. I don't know of any way that re-sizing the window would break the EULA but CCP is hard to pin down on a lot of things.