I have just bought a Lenovo i7 Laptop with 500 GB hard I have installed Windows 8.1 on Partition#1 of 360 GB and the remaining 95 GB is Empty I want to install Ubuntu 14.04. how long will it operate successfully and is 95 GB good to go (if I install latest java IDE). And what if I format Partition#1 after installing 14.04 will Ubuntu stay there with out any affect.
how long will it operate successfully
Well.. technically Ubuntu 14.04 will be supported until April 2019. So if you do not mess it up yourself you can stick with 14.04 for a few years ;)
and is 95 GB good to go
More than enough. You can run Ubuntu comfortably with 25Gb. The Ubuntu base system itself needs about 10Gb to work without running out of space.
if I install latest java IDE
That is not going to cost you Gb's so you should be fine.
And what if I format Partition#1 after installing 14.04 will Ubuntu stay there with out any affect.
Yes. If Ubuntu is installed elsewhere (ie. not on P#1) it will remain there. 1 thing though: if you delete the bootmanager (grub) you will need to re-install it for it to show all the operating systems again.