You need to provide information such as your graphics card type or anything
else relevant when asking for help. Otherwise we are firing blanks and it
wastes time.

Sorry about that. I wasnt thinking obviously. OK here is the model of the
video card. Its an Asus Nvidia 210 silent PCI-ex 16. As for the border
its the bar that is on top of for example Firefox. It is the Mint Green
and is on the same row as the close X. If a screenshot can do the entire
browser I can do that if need be,

OK - that's the Mint colour scheme so you'll need to install a
different theme that you like better, don't think you've much option
around the colour of that bar but you can try customising the theme.
Not sure where it is in Mint but try [ System / Preferences /
Appearance / Customise ]

BC> As for the border its the bar that is on top of for example
BC> Firefox. It is the Mint Green and is on the same row as the close
BC> X.

Did you pick the Debian Rolling Release or another one that picks Green as their
main color? There should be ways to pick your own choices if you prefer.
Depending on the Window Manager it could differ. For Firefox you can find
Preferences under the Edit Menu, on Windows it's Tools, then Options.

Right now I'm working on my PcLinuxOS LXDE computer, but typing this on my
Ubuntu 10.04 Gnome computer.

I am just making a stab in the dark because I am not using Mint currently.
Is it the top panel or below the top panel (the window titlebar). Can you
tell us which Mint desktop environment (GNOME Shell, MGSE, Cinnamon, etc)?
Mint used to be a straightforward distro but it has gotten complicated by
offering too many desktop choices, IMO. When you say it is green, is it
themed green or is it a solid unsightly green bar? Does it appear with
every application or just FF?

If it has a top panel and a side launcher (called Dash) it is GNOME shell.

This may help describing it if it is GNOME shell:
https://live.gnome.org/GnomeShell/Terminology
Cinnamon has a bottom panel like this: http://cinnamon.linuxmint.com/
MGSE looks like this:
www.linuxmint.com/.../lisa_light.png

Assuming it is a driver issue and not a theme: This is just a GeForce card
and it is well supported with drivers. If this was my problem then I would
start troubleshooting by looking for another driver. Click on applications
at the top left and Type Additional Drivers in the search box on the top
right. When the application opens it should show if there is a recommended
new driver. Install it and re-boot. If it does not work for some reason you
can go back to the old one the same way or try a different one. Do not
install a driver outside of these ones unless you are desperate and know
what you are doing.

If it is just theme issue then go to Gnome-look.org and download a new
theme more to your liking. You can manage themes easily by installing the
GNOME Tweak tool.
www.techdrivein.com/.../...manage-gnome-shell.html

Could just be the desktop theme, Mint has always favoured green due to
the name :-)

Particularly a better explanation
of what you are seeing other than 'green border'.