No. You cannot use Tata Indicom CDMA network sim card in this phone.
No. Samsung Metro XL does not have WiFi.
You can store up to 1000 contacts in Metro XL. In addition, you can store up to 250 contacts in each of your sim card. So, if you are using 2 sim cards, in total you can store up to 1500 contacts.
No. Samsung Metro XL does not support Nimbuzz chat messenger.