Should I Update?

Yes, you should. More often than not, it's safer to install the updates than to not (unless you're in a situation where you cannot afford to have a problem, such as the day before a presentation, or while on vacation).

As far as your last questions are concerned: it doesn't matter... it's easiest to download from software update and then restart, and that's what I do.

 

um yes you should install the updates right away. your machine is vulnerable to security threats that apple has acknowledged and patched with these updates. (except garageband which adds iphone ring tone capability).

you thinking its unsafe to install these updates is either a thought process left over from using windows or reading problems that other members have posted about after installing some updates which you owned up to.

you have to remember that forums like macrumors will sometimes be filled with users reporting problems after updates. but this is usually the minority of the Mac OS X user base as people that have no problems dont usually post about it . but there has been a couple of exceptions i have seen .

i would say its better to update via software update as its automatic and you dont miss any updates that may be crucial to your machine. if for any reason an update doesnt show in software update you can always download from apple.com. but some users may think that they need an update when they actually dont. this is why i think its better to use software update. also i think its better to restart after an update because in Leopard you will notice windows showing you the installation and sometimes asking to update the boot caches before it restarts. im not sure if it does this when you shutdown. so to be safe just restart.

i have never had any problems with software updates as i usually keep my machine clean of any system hacksies or apps that i know ill slow down my machine. if you happen to come across any problems installing these updates (there's always a chance that you will) you can always ask in the forums.

 

Besides, if you machine is still under AppleCare, and an update breaks something, you simply take it to an AppleStore, and they will take care of it.

The people that had their SuperDrives bricked by either the SuperDrive update or the 10.4.10 update could get them replaced under AppleCare.

Not updating is just asking for problems, and most advice that you will get will be dependent upon you running the latest update since some of them add functionality that you wouldn't get otherwise.