I have come across many different SQLs but I cannot decide which one is the best to use.
Which one is most recommended for beginners?
Since you are just a beginner, I would recommend that you try out first the tutorial or you could buy and read books. For online courses you could visit this website: http://www.sqlcourse.com/index/html
You could also buy one of the excellent books on getting started with SQL Server through B&N or Amazon website. After installing your SQL Server, work through the tutorials in Books On-Line (known as BOL).
You could buy the SQL 2008 Server 2008 Express on Win XP x86 so you could start with some of the basic exercises, if you wanted to learn some administration works, reports, queries and etc.
I believe that Oracle SQL Developer is the best tool to get started with SQL. First of all it’s free and it will run on pretty much any platform like Windows, Apple, Unix & Linux. It is the most commonly used SQL around the world and you only need to extract the files and run it.
It’s user friendly and very simple to use. The wizards and simple GUI makes all the code works easier for new learners. There are few useful tools come alongside with it. There are many learning resources available for beginners and you can learn by yourself using the Query Builder.