All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
We will answer your questions in the following points:
1- If you were able to repay your debts within the period of two years and you did not do so, and it was an immediate debt, then you are wrong for this delay. Afterwards, if the creditor agreed that you repay your debt by installments, and it is predestined that you die before repayment and you did not leave any money, then we hope that you will be included in the Prophetic narration which reads: "Whoever takes people's money with the intention of repaying it, Allaah will repay it on his behalf, and whoever takes people's money with the intention of spoiling it, then Allaah will spoil him.” [Al-Bukhari]
2- Changing one’s surname is not permissible as we clarified in Fataawa 89932 and 85803. Nonetheless, you should endeavour to convince their father to sign the papers. If he is convinced, then praise be to Allaah, and if he insists on refusing, and you are obliged to change the family name and you have no other alternative to achieve this objective, then it is permissible to change the family name, but you should avoid being subjected to any problems or harm due to this action, because it is an obligation to preserve the original family lineage so that people’s right will not be lost and so that there would be no confusion.
3- In regard to how to memorize the Quran, we have already clarified this in Fataawa 87885 and 83985.
4- It is permissible to have a T.V. in order to watch programs that do not include any prohibition, and sometimes it might be better not to watch T.V. and this is in regard to whomever fears that he will be enticed to watch what is not permissible. Similarly, it is permissible to use the internet in permissible matters like contacting the family, and being entertained by games that do not include a prohibition, like music and the like. For more benefit, please refer to Fataawa 81723 and 84494.
5- If the creditor agrees with the debtor to repay his debt by installments every month, then it is permissible for the debtor to donate in charity what exceeds the fixed monthly installment as long as his donation does not affect the due installment or the forthcoming installment.
Allaah Knows best.