I use windows 7 pro, no restrictions no hassle and I got it at a bargain price.
I know it's not free, but to be honest I'd sooner pay a bit of money to save the hours I'd waste trying to get ubuntu to do what I wanted, it does everything you want and a lot more and it's never fallen over.
Obviously if you know your *nix then it's less of an issue, but every time I have tried, I come across problems that should be really simple to fix and either took hours or have never managed to fix.
By the way this isn't a which is better thread, so lets not start that debate please
Just thought I'd post my reason for paying for Linux