As far as I know you can't change the install path for windows live essentials as it's generally part of the windows updates.
As Beso said, you'd be far better of moving your personal data to another drive to make more room on your C drive, if you're that low on room on your C drive then it's going to cause you other, more serious, problems sooner rather than later.
You've not said what version of windows you are running, but it's very easy to move your documents folder to a different drive in all versions.