Hi,
I have just installed mint 17.1 x64 and there are a couple
of problems.
I have limited vision and i have to connect my comp to my
47" tv but I seem to be missing a fair bit of the the
desktop all around the screen, I can just see the the very top
of the taskbar at the bottom of the screen and about 3/4 of the
icons on the left.
I have been able to increase the size of the bottom panel so i
can see the taskbar icons butitis not ideal.
Is there anyway to shrink the screen to let me see the whole desktop?

Also I need to use the on-screen but when I turn it on it takea
up the whole bottom half of the screen, Is there anyway to have
a floating keyboard like the one in Windows?
Thanks

In Mint Mate, there is a Control Center which has a Monitor option where you can change settings for an external monitor/TV. If you are not using the Mate version, you should have a System Settings option or similar with either a Monitor or Display option in which to adjust settings.

If that doesn't work, try changing to the "fglrx" graphics drivers and check the options in the "Catalyst Control Centre" -- a [SOLVED] thread on the Mint forums uses this method.
http://forums.linuxmint.com/viewtopic.php?f=49&t=174417

Is it a newer model tv? Most of the newer model tv's have a setting 3 settings "Normal, Fill Screen & Over Scan".