I think we might need to define what you mean by a "house defensive gun." Usually, I think of house gun as what is on the night stand by my bed at night and on top of a book case near the door during the day. For that usage, there are definitely better choices than a G36 including a G30 (my favourite) or a G21 as Tecolote recommended. There is no need for a weapon as small as the G36 in that role.
Now for 1911s - I have never had a reliability issue in any Colt (1991A1, "Enhanced" or XS) I have owned. They have all been reliable straight out of the box even to feeding the notorious "flying ashtrays," but if I bought one for home defense I would fire several magazines-full (of each magazine I planned to use) of the ammo I planned to use. (Actually, I would do this for the G30 or any other weapon I was going to use in life or death role. I would test the 1911 style or G36--it appears to be somewhat finicky about ammo--a little more thoroughly than I would a G30 or G21.) The weakest reliability link in the 1911 is usually the magazine (and I would say they are more "fragile"--susceptible to damage than a Glock magazine). Again though, for your stated use, I would probably toward a full-size 1911 over a Commander--particularly as a first one--(and definitely over anything smaller than a Commander). The full-size models tend to optimize the ammo performance (the nominal barrel length for .45 ACP is five inches), will have a slight reliability (probably not over the Commander, but definitely over smaller models) and are easier to shoot than the "lightweight" versions of the Commander. As a reference point, there is far less size difference between a full-size 1911 and a Commander than there is between a G21 and a G30. (And just FYI, I have never been a Commander fan which my colour may remarks somewhat.)
Now some minor "compare and contrast" - If you are familiar and comfortable with a Glock and have limited or no experience with the 1911, I would stick with the Glock for a house gun--what you do not want to do is roll out of the bed at 0230 and have to figure out (remember) how to operate the weapon in your hand. The 1911 will need to be in Condition 1 (cocked and locked) with the manual safety engaged where the Glock will be ready to go. When you disengage the manual safety, you will have far better trigger (lighter, less travel and "crisper") than a Glock. These are very nice attributes at the range or when you are fully awake and fully functional. I am not so sure they are what you want when you are awakened by something going "bump in the night" unless you are intimately familiar with them. (To be honest, I would go so far as to recommend the NY1 for this application--house gun--in the Glock.) A G21 or G30 would give you a 25% (a 75% increase with high caps) in ammo capacity. I don't really consider it a big issue, but it might be factor is someone is kicking down your door and you don't have a spare magazine in your pocket (when something does goes "bump in the night," I grab my flashlight and weapon but not a spare mag--probably not "best practice" on my part).
If someone told me year ago I would be arguing the merits of a Glock over the 1911, I would have called them a liar. Now, if you are buying just for fun and to broaden your horizons, by all means, go get you a 1911. I do applaud your acumen in selecting the .45 ACP over the 357 Sig as a defense round (just to aggravate the 357 Sig fanatics
).
