Shia view on every person is always based on his obedience or disobedience to Allah and The Messenger (SAWA). Khalid bin Al-Waleed spent most of his life fighting against Islam and the Prophet (SAWA) since he was in Makkah till he surrendered to Muslims. Khalid bin Al-Waleed fought against Islam in the battle of Badr and was captured by Muslims ( according to the famous Sunni historian Al-Waaqidi). He fought against Islam in the battle of Uhud and caused a disaster for Muslims. Even after he was forced to surrender to Muslims, he committed crimes which made the Prophet openly dis-associate himself from the acts of Khalid. (Saheeh Al-Bukhari; 7189).

Khalid ibn Al-Waleed was sent by his friend Abu Bakr to fight against Malik bin Nowairah who was a pious companion appointed by the Prophet to collect the Islamic dues from his tribe Bani Tamim. Khalid despite knowing that Malik bin Nowairah was a Muslim,he killed him and took and slept with his wife on the same night which is a crime against basic rules of Islam. Omar ibn Al-Khattab called Khalid: O enemy of Allah, you killed a Muslim man then slept with his wife. I will stone you. (Tareekh Al-Tabari 2:504 and Al-Kaamil by Ibn Al-Atheer 2:359).

Khalid ibn Al-Waleed is been praised by some Muslim groups for political reasons because of his enmity against Ali ibn Abi Talib. He was one of the persons who attacked the house of Fatima and Ali and he was involved in a plan to kill Ali which could not succeed.(Kitab Al-Sunnah by al-Khallaal 3:505 and Tareekh Dimishq by Ibn Asaakir , V.41, P.46 and Al-Ansaari by al-Sam'ani 3:95).

Wassalam.

Yes it is very good to pray for the guidance and forgiveness of your parents.

It is also allowed to pray for deceased Muslim for forgiveness and mercy from Allah (SWT).

Wassalam.

Yes it is permissible to cut nails and hair while fasting.

Wassalam.

It is obligatory to fast the whole days of the month of Ramadan if you are not ill nor traveling. You must obey Allah and never disobey Him to please any one else even your parents. You can not commit a sinful act to please any one.

Wassalam.

If your adult daughters find it difficult to wear full Hijab at home in front of the Non Mahram man, you must protect them from falling in sin of being seem by him with out full Hijab. You must arrange for him another place to live, away from your adult daughters.

Wassalam.

Allah's Knowledge and Power is every where and He is with us wherever we may be. Allah says in Quran: (And He is with you wherever you may be).(Sura 57, verse 4).

Wassalam.

Our concept of day and night with us human beings, is not necessarily the same concept of day with Allah who Created every thing including the time before creating the earth and sky. Time was created before earth and sky and that time had got its day which is different from our day.

'Wassalam.

Following Ahlul Bayt is in fact following the real teachings of the Prophet (SAWA). None of the four Sunni sects (Hanafi, Shafi'ee, Maaliki and Hanbali) were existing during the time of the Prophet, while Ahlul Bayt were living with the Prophet and practicing his teachings.

Details of the rules and worship can be easily found in many websites e.g. www.Sistani.org and www.Al-Islam.org and www.shiasearch.org

Wassalam.

Every human being needs a constant bond with His Creator Who is showering His bounties on him, through remembering and worshiping Him. This constant bond is the only way to tranquility and peace of mind. Tahajjud is a special prayer performed at night when people are asleep or indulged in their desires. The sincere believers enjoy at night talking to their best beloved who is Allah through Tahajjud ( Salat Al-Layl) where they get spiritual satisfaction and happiness, and get stronger in their day to day life challenges. The benefits of Tahajjud are more than our ability to count. It is the way for every good in this life and every good hereafter. Hadeeth from the Prophet (SAWA) when he was asked for the way to health, wealth, peaceful and respectful life and every good in this life, he replied: Night Prayer. He was then asked about the way for success and High degrees in Hereafter in Paradise,v he replied: Night Prayer.

Wassalam.