Is it a good idea to download Linux on my PC instead of windows 7? which one?
In general, the advantage of running linux (in my biased opinion as a linux user) is that there are literally thousands of pieces of software to choose from that you can install easily and that are free. When I install linux on a new machine, I have a list of about 120 applications that I install, and it takes 5 minutes of my time to initiate the downloads.
Ubuntu is the easiest version of linux to get running.
For scientific programming, the advantage of linux would be that a lot of the tools you need (compilers, libraries for numerical stuff, ...) are free and easy to install, whereas on windows it's pretty nontrivial to get a working development environment without paying money.
You could always dual-boot them, and get the best of both worlds.
This is a good way to start. Learning Linux properly is a time commitment. In my opinion, it is well worth the effort, but many people give up because it takes longer than they expected.
If your future profession is going to have anything to do with computers at a level deeper than a browser and a spreadsheet, I would say that learning linux is a very good idea. However, as with Ben above, I am also biased.
Ubuntu has just made a major overhaul of the user interface and they are still working the kinks out. I might suggest xubuntu or kubuntu as good alternatives.
If your computer is fast enough, you can install VirtualBox and run a second operating system in a sandbox. It is a great way to go further than just playing around with the live CD. It is nice for testing out a new distribution without having to repartition your hard-drive.
I haven't found this to be true. At least, I can't think of any language I've wanted to program in that I couldn't find a pretty good IDE for windows for free.
Shell scripting on linux can be pretty handy, and a lot of programs you'll run in linux can be run from the terminal so you could even SSH into your linux machine and do just about anything you want. Which means if you have a smartphone you could control your computer from anywhere :D
Personally, I just like the feel of linux better, once I get it up and running the way I want. Can't really put my finger on one thing in particular. Mostly, I choose which OS to use based on the software I want to use at the time; for instance, in my lab we have programs written in C++ which call a few windows-specific functions, so rather than porting them to linux I'll just use windows.
Edit: And I just started using Scientific Linux (http://www.scientificlinux.org/) which is based on Red Hat Enterprise Linux. Pretty much as easy as Ubuntu to use so it's worth checking out.
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