Now, please answer a few questions: Do you want just a home defense gun? If so you can't beat a 12 ga shotgun. PERIOD. If you're going to secure a lawful concealed weapons permit and carry it on your person, it depends on your body type and the size of your hands as to how comfortable you're going to be with the various available firearms. Also important, especially for a novice is going to be your weather. If it's hot and muggy like it is where I am in South Florida; do you really want to have to wear a photographer's vest everywhere you go? Or a sport jacket? You could opt for the belly bag, but that's an incredibly slow draw and especially under life and death stress, could prove fatal for you.
As a general rule, the .22 makes a great weapon to use for an assassination by a pro hitter. The MOSSAD uses them to eliminate terrorists and other unsavory enemies. But they shoot them thru the EYE, twice! The rule of thumb is to buy the largest caliber you can shoot accurately and safely and comfortably. A .22 magnum may approach the same velocity as a .38sp, but lacking a similar cross sectional density of the actual projectile, it has none of the so called "stopping power" of the larger round. And as has been mentioned here, the .38 ain't such great shakes either. Just remember: Accuracy, power and speed is what wins hostile confrontations. That and a good tactical mindset. What does all this mean? TRAINING AND PRACTICE!!!
When I teach a class, I usually let the student use a variety of guns that I own of various types and calibers. Invariably, ONE of them will leap out as THE ONE...just like King Arthur and Excaliber! So it shall be with you and for that reason so as to avoid inappropriate influence, I don't recommend specific makes of guns.