Ok... to address a few of your points.
First Here is a link to Hickok45's youtube.
Go to his playlists and look at the "basics" and "gun safety" videos. He has a lot of good info.
Here is a thread I did on cleaning if you need any info on that.
As was mentioned... Single action, double action, SA/DA, DA only, Hammer fired, striker fired... Its not hard to learn, and you have started that process. The videos on the youtube channel I linked has a run down and demo so its easier to grasp rather than reading.
Polymer... its been around for over 20 years... its proven itself, but buy quality brands. Some polymer guns from cheaper brands are not always designed with longevity in mind, but pure size and weight. The Kel Tek pistols come to mind, pocket sized, and very light, but are not designed for years of regular range use.
I like the XD/XDm because of how it is designed... there is a large chunk of metal in it that holds all the guts and has beefy slide rails in it. It is built well, and will last a long time... Competitive shooters have put tens of thousands of rounds through a single XD and Glock with no major parts replacements or problems. (springs do need changed after several thousand rounds as preventive maintenance... 6000-10000 rounds or so depending on model)
Longer barrels are more accurate and provide more velocity to the round. Accuracy comes from a longer distance between front and rear sight. (sight radius)
The 1911 can be a little finiky for a couple reasons:
It was never designed to feed hollow points...
It was designed to be build with parts fitted by hand...
A 1911 built to the original specs using the original design magazines will feed FMJ very very reliably... HP ammo can be difficult to feed because the shape can throw off feeding geometry. Modern pistols are designed with this in mind, the 1911 wasn't. There are ways to get it to feed HP, tweaking of the original feeding geometry design, or redesigned magazines. These tweaks are compromises... as they need to make the pistol feed many types of ammo even FMJ, and while the quality makers mostly get it right, sometimes there is tweaking that needs done after purchase...
Hand labor is expensive now a days... so most firearms are made from part that are machined, cast, or forged, and modern techniques make for tight tolerances... but variations exist in the parts. Then the firearms are assembled on an assembly line. Sometimes a firearm is assembled with just the right combination of parts in which the tolerances add up in a way that causes issues.
There are some companies that hand fit 1911s during assembly... but you are going to pay good money for that. SA does do some models with hand fitting, they start at $1500 and up depending on the level of detail in the fitting and features added. Nighthawk Custom hand fits every pistol they make... but they start at $2500 and go up from there.
Hollow points are indeed the preferred choice for defensive use... but they are expensive, about 3 times the cost of FMJ target ammo. Winchester PDX1, Federal HST, Speer Gold Dots... they are on the top of the performance figures, and generally feed reliably, while still being easier to find and not overly expensive.
The rule of thumb is that any pistol you plan on using for defense... you need to pick a HP ammo you prefer. (usually one that is good performing and easy to locate locally) You then need to fire at least a couple 50rd boxes of this ammo through your pistol, and more if you can. This is to test to see if it feeds reliably in your pistol... as no two pistols are exactly the same, even if they are the same model. You may find one that feeds Gold Dots well but not PDX1s for example.
My preferred 9mm defense load is 124gr +P, and currently it is Federal HST, as I found a very good deal on it. Here is a post of mine talking about ammo and the different types and things to look for.
Since you expressed interest in the CZ.
CZ USA's website handgun page.
The original was the CZ 75, and they developed different versions from there. Hickok45 has a review on the 75. CZ claims that the CZ 75 is the most widely used service pistol in the world... Jeff Cooper, which many/most feel is a high authority on defensive/combat hand-gunning, considered the CZ 75 the best service pistol in the world. The 75 has an "in frame" slide design that is different from most pistols and aids in its accuracy and ease of shooting.
They are made in the Czech Republic... and if you feel funny about that... don't be. The company has been around for over 100 years, and not only do they have a long standing reputation for quality firearms, they have designed and built some well known military firearms... the British Bren machine gun for example... the CZ 75 is as well... seeing as its also one of the most copied handguns ever with only the 1911 having more... The Czech are known for having outstanding military arms. They are the only Warsaw Pact country (part of the USSR) that did not adopt the AK47 when prompted to by Moscow. They designed their own rifle, the VZ 58, and many feel it is equal if not better than the AK... it definitely has some features that I like better than the AK.
They have several "duty" sized and full sized, pistols in steel, aluminum, and polymer frames. The P-01 is a duty sized with aluminum frame and accessory rail. It was designed as a new police issue weapon, and several around the world use it. The SP-01 is a full sized steel framed big brother to the P-01... the full size is probably your best bet, the longer barrel and extra weight will aid shoot-ability.
The pistols are designed as DA/SA, which I like in a pistol I will use for defense. (I like striker fired as well)
You can get the CZ with a manual safety, which allows you to insert a loaded magazine, chamber a round, and you then have the option to engage the safety and have it "cocked and locked" like a single action 1911, or you can manually lower the hammer and have it ready with DA first shot and SA for follow up shots. Many like this as they do not need to worry about "forgetting" to disengage the safety when under stress if they are in a defense situation.
Small problem though... Manually lowering the hammer involves some risk... the risk that you will somehow let the hammer slip from your control, and accidentally fire the pistol... There are techniques which limit this risk to near 0, but it will always be there, and lapse of concentration due to complacency, is the usual reason for negligent discharge when manually lowering the hammer.
This is why "decockers" were invented... And CZ offers decocker models.
Decockers lower/decock the hammer for you mechanically and safely. For a new shooter or someone who is uncomfortable with manual decocking, this is a good thing.
Here is the official CZ forum.
It is a good place for info for CZ firearms.
If you can't tell... I really like CZ pistols.
I think they are superior to the Beretta 92... and while there may be many other pistols that are just as accurate or reliable... they do not approach the comfort and ease of shooting that CZ has... Or that can match the performance at similar price levels. Sigs are excellent pistols, but cost several hundred dollars more than a CZ... I even saw a review of the SP-01 where the guy said that anyone that uses a CZ in competitions is cheating, because they are so easy to shoot.
Another thing to consider down the road is getting a 22lr pistol for cheap practice and general fun. The Ruger Mark III or SR22 are good choices, and can be had for around $300... Or if you do buy a CZ pistol, you can pick up the CZ Kadet conversion kit, for about $250... it allows you to convert your CZ 9mm into a 22lr for practice.