SQL Server 2008 Express R2 Having trouble installing any advice please??

Question

I have tryed installing SQL Server 2008 Express R2 which i have downloaded for free from MS Dreamspark as I am a Sortware student in Ireland, however I have problems installing it on my machine. I have followed the steps I found online for installation but after completeing the steps and seeing that it is installed but when i reatart the computer there is no Server Management Studio or indecation of Express sql amoungst the other MS programs.

What am I doing wrong...or am i missing something simple???

Kind regards,
Kieran