Quick question on speed of fermentation

So I am only on my second extract+specialty grains beer. First one was an ESB brewed with London Ale yeast (8lbs LME, 2lbs steeped specialties). After I pitched the yeast, visible fermentation started (evident bubbling in airlock) about 24 hours, got rather intense then slowed down/stopped around day 4. Ambient temperature was around 74 degrees so a little on the warm side. Taste was still good, maybe a bit estery but I am not sure what that even means having only started home brewing.

This current batch I am working on is an IPA with 9.9lbs of LME and 4lbs of steeped specialty grains. I pitched 1 vial of California Ale yeast then 24 hours later pitched a second one based on recommendation (1.071OG). Fermentation started about 30 hours after initial pitch and got somewhat going, however has been like a crock pot ever since - low and slow. Been over a week and a half and still going about 1 bubble every few seconds. Smells great though! This batch has been fermenting at a much cooler 62 degrees which I think may explain the slower rate.

So I know that there is no problem, I am just trying to learn more. How will a lower temperature fermentation/rate differ than a higher fermentation temperature/rate?

Also I want to take a gravity reading sometime once (if!) the fermentation stops. Other than sanitizing the turkey baster, any recommendations for keeping the beer safe when I take the lid off?

The beer will be fine when you take the lid off. There is a layer of CO2 sitting on your beer protecting it.
Here are my tips: Sanitize baster, pop the lid, take your sample, read your hydrometer, drink sample.

As you've noticed, yeast will go gangbusters at higher temperatures but that's not always what we want in our flavor profile. I LOVE california ale yeast fermented at about 62 degrees- clean, without esters. Esters are the name of the "fruity" flavors you get in some yeast strains, and in beers fermented at high temperatures. Often, the fruit is reminiscent of bananas. Slow and steady wins the race, in my opinion! A "hot" ferment can also produce fusel alcohols and other nasty flavors. I have a stick on thermometer (like an aquarium themometer) on my fermenters, because I've seen the temperature of the beer in the fermenter be as much as 8 degrees warmer than the air temperature, due to the heat fermentation produces!

One way to get around using two vials of yeast is by making a starter. A little dry extract and a couple of days, and you can easily grow enough yeast to ferment any size batch. In fact, it might not be strictly necessary, but it's recommended to use a starter with any size batch when you use liquid yeast.

No reason to worry when you remove the lid to take your SG readings. Just be sanitary, and try not to sneeze into it! Oh, and don't return your reading to the fermenter. You can take a taste and see how it's coming along. Then pour out what you don't drink. I always sample my wort, and then the beer as it progresses. With time, you can taste a wort and say, "Oh, wow- this is going to be GOOD!"

Thanks for the responses!

Yoop, yeah I forgot about a starter. Actually didn't consider a starter until AFTER I pitched. I posted online about it, and people recommended either a starter or an extra vile. Since I already pitched, decided I should go with the extra vile. Regarding making a starter, lets say your vile comes with, oh, 30 billion cells. You make a starter, is it safe to assume your amount of cells double?

I may be able to find this in Palmer, but why do the number of starting cells matter? I mean theoretically, if you pitch ONE cell, shouldnt it multiply enough in the wort to make enough cells anyways?

Side note, I'm loving the smell coming out of my airlock. Has evolved nicely over the weeks... I am looking forward to this beer already!