My cd drive always ask for cd ,if I remove cd then a small window pop up and doesn't able to close .always require to insert cd

It must be due to pending installation see which intsallation was stooped midway and remove it form

Start--Run--Msconfig--

I've seen many viruses also do this. Am almost certain of it.

Make sure you have an anti virus and it's updated.

After a full scan of the system also download a extremely nice program call Malwarebytes Anti-Malware and do a full scan with it as well.
Link to Download -> http://download.cnet.com/Malwarebytes-Anti-Malware/3000-8022_4-10804572.html

Hope this helps

Cheers