First off,your wife does NOT have to answer the door.
There is no law that says you have to answer any door unless it's the police,and I mean in uniform with a cruiser outside the house or apartment.
Secondly,if you have ground floor windows (or any windows) that can be seen from the street ( or an ajoining apartment),they all need to have blinds on them.
At night,anyone from the street can see inside any house from a block away or more and see anyone and anyhting inside the house whose windows do not have CLOSED blinds.( even from a slow moving car passing by)
As others have said,you need to beef up the doors security options.
A chain of any kind is really no good.
It's much better to have a peephole with a bright light on the front porch and to never unlatch the only security she has at home alone,that door latch.
Get a quality deadbolt installed-double sided lock if the door has windows-front door and back door too-even if it's a second story porch door.
Regular door handle locks really are very weak.
Some how,your wife is being seen from the street or men in the neighborhood are commenting on how nice she looks and that you are never home.
That's why you've had two instances of men coming by the house unannounced and unwanted.
The guy with the 'pizza' is of real concern.
He might have been casing the neighborhood by car one night and seen right in your house and right in at your wife at some time.
Get the phone set up so she can call 911 right away but she defintely needs a firearm and not a 22 handgun.
As others have said a 38 revolver-Bud'sgunshop.com is selling Model 10 Smith and Wesson's right now used for around $265 in good shape.
But really,if you and her can get together and she can train to use a shotgun,a shotgun is preferable.
And don't train to shoot just once and wait-train to fire until the guy goes down and to counter any stupid friend he has that wants to make some point about seeing his stupid friend just get himself killed trying to rape your 'defenseless ' wife.
What we are talking about JUST happened and thank the young lady that she saw a threat coming and got herself prepared for it becuase she saved her own life and that of her small child as well.
Get prepared and change how you present your home in the neighborhood.
People should walk by and see closed blinds,lots of lights and feel like-what happened? Looks kind of like someone's waiting for me if I do something stupid there.
Then the criminal element USUALLY moves on.
Sometimes they don't and that's where your wife stands away from the door so that if some idiot crashes through it,the door won't hit her and she defends herself and the home too.
A woman with a shotgun who knows how to use is no one to mess with.
One last thing-you will never know who is talking to who- is talking to who- and just how the information about your wife being alone is getting spread around.
DO NOT make what you are doing public information.
And when people start asking weird questions about -does your wife have a gun? Are you guys getting guns or alarms or stuff like that?
You might have your answer about who is the loudmouth who is threatening your wifes safety and your peace of mind.
Tell your wife to be careful what she says to her girlfriends as well about when you are not home or the like.
And just because a guy looks harmless and normal-even if you know him as a friend-if he has no reason to be at your door while you are not home THAT YOU ALREADY TOLD HER ABOUT--tell your wife to not open or answer the door.
Whoever it is can leave what they are dropping off just out the door and leave.
Your work schedule and when she is alone is your and her business ALONE.
For all intents and purposes,I try to make my house look like you will get killed right away if you try to break into it.
Lots of lights-some motion activated-no bushes next to the house to hide in,cars parked so I can see around all of them from my kitchen window,my grill and my trailer are both chained down and both have been targets of thieves who failed-three times with the trailer,once with the grill.
My two little Pomerainian dogs have helped too.
Little suckers can hear cats walking on concrete sidewalks for Christs sakes.
Anyway,you get the drill.
Prepare and tell NO ONE what you are doing.
I always know where my Model 10 is and it's loaded and I can shoot it very well if need be.
But I prefer to convince the idiot thief to move on.
Less mess to clean up.