Need these restrictions

Hi all. I am new to this site and Community Forum. I don't know if this is the right section to post this question and apologize for that.

Now on to the question. I am a student IT intern who started working three months ago. My Admin, without realizing that this could be a tough task, told me to use Group Policy to restrict and block certain things for new students and staff coming in. I have never used Group Policy before with no experience of it. My experience to work as a IT has been coding and programming. Anyway, there are alot of things he wants to be blocked/restricted but these have been the most trouble some: block sites like Facebook or YouTube, restrict software installation, no media access with or without Windows Media Player or any other program, and last, Admin account have no restrictions.

So, please can anyone offer any help? I have been unable to do anything about these. If it is possible for you to provide a step by step procedure on how to do any of those, I will really appropriate it.
By the way, my workplace is run as Workgroup(s). The OS is Windows XP Pro Ver 2002 Service Pak 3. I will be imaging this and installing image to other computers.

Please help. I will appreciate it.
Thank You

i think you need to run an domain in order to do some thing with group policys with atleast one domain controller.