re: Recommendations for buying first handgun

Ed,
As you've seen, you're going to get a gazillion different recs for a gazillion different guns. Most handgun owners have a tendency to think THEIR gun is the best gun for EVERYONE. That's only natural. OTOH, what YOU want to find is the best gun for YOU.

First, you need to do some research about different gun traits so you can simplify your purchase by deciding WHAT you like (or maybe, what you DON'T like). Then look for the model(s) that fit your criteria:
Reliability record.
Action: DAO, SAO, DA/SA, Striker fired?
Frame: Steel, polymer, aluminum alloy?
External safety levers: Yes or no? grip safety?
Mag capacity?
Accessory rail: yes or no?

The main guns I'd point most people to would be: Ruger SR series
S&W M&P series
Glock, esp M17 and M19.
Sig (I can't keep track of all their different models......)
Springfield Armory XD series, especially the Service Model
Beretta
CZ
ETA: H&K (may be too expensive) and Walther.

Get a full size frame gun, not a compact. Since you're not going to carry it, I'd suggest a double stack magazine configuration, as long as you find one that fits your hand. Handle and shoot as many of the contenders as you can. And remember, a nice revolver in 38 Spec/357 Mag is NEVER a bad choice for home defense/self defense.

Of course, don't forget that a shotgun in 12 or 20 gauge is prolly the single best home defense gun.

Caliber? The rounds that have the best track record for self defense use are 9mm, 357 Sig, 40 S&W, 357 Mag, and 45 ACP. In a semi-auto, I'd usually recommend 9mm. When ammo's available, the 9mm is less expensive and easier to find; it's also easier for most to shoot well, especially w/ rapid, accurate shots.

The Springfield XD service model you mentioned is a fine gun. I had one in 40 S&W before finding out it was not suited for me concealed carry.

Really good info here.
Semi-auto's LINK
Revolvers LINK