XP freezes after boot.

Greetings all!
1. When I 1st start up the computer or reboot, XP freezes at the desktop. I have to do ctrl+alt+delete to do a logoff twice from the same box to logoff, then when I log back on, everything works fine.
2. I can only use my ISP once, i.e., if I want to use it after I’ve exited it, I have to reboot.
3. I cannot access the ‘root directory’ at the command prompt.
4. Is there a way to read my ‘product license key’ from the XP CD or the harddrive? My computer manufacturer failed toinclude it w/ my new PC! I am trying to obtain it from them tho.
It seems like the ‘OS’ needs to be reinstalled, but I can’t do that without the license key.
I hope you can help!
Thank You!