Im a first time mac user.

I ve purchased a Mac Pro today during mid-day..

The thing is,I had to setup a Windows Xp 64.
I first have partitioned the 350gb disk by bootcamp,then ran the windows cd,restarted,Finally ,I have chosen the mac to install the Windows on drive C:
Is it ok so far?
Guess I have made a mistake..
Heres the problem

I hold X during startup but I cant choose which operating system I want to use.
I have ordered the application 'parallels' already.

Please tell me what I can do to see both operating systems.

Thanks in advance