It is extremely simple to test out latest SQL Server 2008 R2. You can even get pre-configured ready to use VHD, which you can download and use it.
This becomes very easy as one does not have to do anything besides downloading VHD and installing it on Hyper-V.
Download Pre-configured VHD – SQL Server 2008 R2 Standard
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Reference: Pinal Dave (http://blog.SQLAuthority.com)