He is confused as to whether he should marry a virgin or a widow

Praise be to Allah.

This depends on the situation of the husband; it may be that marriage to a widow is more suitable for him, and better. 

The widow may be a lady of religious commitment and good character, such that you would not want to let the opportunity to marry such a woman “slip through your fingers”, and you could not find a virgin of such religious commitment and character. 

But generally speaking, the Prophet (peace and blessings of Allaah be upon him) encouraged marriage to virgins. 

There is the story of Jaabir (may Allaah be pleased with him), whose father had died, leaving him with sisters. In his case it would not have been suitable for him to marry a virgin who was young like them. So he wanted to marry a woman who had been previously married, who could take care of them and look after them, and the Prophet (peace and blessings of Allaah be upon him) approved of his decision. 

It was narrated that Jaabir ibn ‘Abd-Allaah (may Allaah be pleased with them both) said: “The Prophet (peace and blessings of Allaah be upon him) asked me, ‘Have you got married?’ I said, ‘Yes.’ He said, ‘A virgin or a previously-married woman?’ I said, ‘A previously-married woman.’ He said, ‘Why not a young girl, whom you could play with and she could play with you?’ I said, ‘I have sisters and I wanted to marry a woman who could gather them together and comb their hair and take care of them.’ He said: ‘You will reach, so when you have arrived (at home), I advise you to associate with your wife (that you may have an intelligent son).’”

(Narrated by al-Bukhaari, 1991; Muslim, 715) 

According to another report narrated by al-Bukhaari (2257), “… so she could teach them and discipline them.” 

According to another report narrated by al-Bukhaari (2805) and Muslim (715): “He said: ‘The Messenger of Allaah (peace and blessings of Allaah be upon him) said to me, when I asked his permission (to participate in jihaad), “Have you married a virgin or a previously-married woman?” I said, “A previously-married woman.” He said, “Why did you not marry a virgin whom you could play with and she could play with you?” I said, “O Messenger of Allaah, my father has died (or has become a shaheed/martyr), and I have young sisters, so I did not want to marry someone like them who could not discipline them or take care of them, so I married a previously-married woman who could take care of them and discipline them.”’” 

It was narrated that Jaabir (may Allaah be pleased with him) said: “My father died, leaving seven – or nine – daughters, and I married a previously-married woman. The Messenger of Allaah (peace and blessings of Allaah be upon him) asked, ‘Did you get married, O Jaabir?’ I said, ‘Yes.’ He said, ‘A virgin or a previously-married woman?’ I said, ‘A previously-married woman.’ He said, ‘Why not a young girl whom you could play with and she could play with you, and you could laugh with her and she could laugh with you?’ I told him that ‘Abd-Allaah had died and left behind daughters, and I did not want to bring to them someone like them. So I had married a woman who could take care of them and discipline them. He said, ‘May Allaah bless you,’ or similar kind words.”(Narrated by al-Bukhaari, 5052) 

Shaykh Mustafa al-Ruhaybaani said:

“It is Sunnah for the one who wants to get married to marry a virgin, because the Prophet (peace and blessings of Allaah be upon him) said to Jaabir, ‘Why not a virgin whom you could play with and she could play with you?’ (agreed upon) – unless there is a reason for which marrying a previously-married woman is better, in which case he should choose such a woman over a virgin, in order to serve that interest.”(Mataalib Uli al-Nuha, 5/9, 10) 

And Allaah knows best.