You'll be happier picking out hardware you know works well with your distribution of choice rather than trying to make Linux work on random hardware. If you already have the hardware, and won't be buying more, check the hardware compatibility lists of the distributions you're considering. You should probably be down to a short list of distributions by now. Browse their web sites for security updates. Also, look at the security mailing list.
Some distributions can do automatic software upgrades over the Net.
This can be a great time saver and a relatively painless way to stay current on security updates. If the idea of upgrading with one command or a few clicks sounds good to you, check to see if a potential distribution offers this feature. Installation Nobody only installs once. As a hobbyist getting started, you might install a couple of times and then blow your system away, either by mistake or because you decide you don't like something. In a business, you'll need to be able to install quickly, either to recover from a crashed disk or to deploy a new system.