Inspiron 9100 - Windows XP issue

As mentioned I have an Inspiron 9100 notebook.

 

About an year back my windows went corrupt and I had to reinstall. Unfortunately I did a complete format before the new install. Now I wasn't provided with an XP CD when I bought the laptop so I had to use a copy downloaded from the internet and use my XP CD key. It all worked fine but alas I have been unable to get my TV tuner card to work. Plus my system information says "Fujitsu Siemens System"!

 

Now how do I go about installing a proper XP supported by dell?

How do I get my TV tuner to work if I won't be able to get a dell XP?

 

Cheers in advance.

Zar.