I want to make an older IBM laptop useful.
Ah! Very likely all the hardware will be automagically detected and drivers will just work. Really.
As suggested by others, get a LiveCD, boot from the CD, and use that to verify that everything is working.
You can also visit Linux-On-Laptops.com and see if your specific model is listed. You can also just use Google (or Startpage) to search for "linux" and your laptop model, and see what comes up.
it would be nice to have a very low function minimalist OS.
If I may suggest, unless it has a relatively small HD, like 4GB, that you not focus on minimalist OS, but instead use LXDE or Xfce, rather than KDE or Gnome, as your "desktop environment".
All the applications from KDE, Gnome, etc, all run just fine in any "desktop environment", since what they're really doing is using the X window system to display. The "desktop environment" just give you the application bar, menu, shortcuts, stuff like that.
You can get really minimalist with "Tab Window Manager", better known as twm, which Debian installs by default even if you choose KDE or Gnome or whatever else.
Summer 2008 I finally retired a 1998 K6 350MHz 128MB laptop that ran the full Debian Unstable just fine. I didn't try to run video, or flash, but audio worked fine, along with OpenOffice, Firefox, and all of KDE. I'm pretty sure your IBM laptop is newer than that, so don't worry.
I gave her the lap top and told her to replace MS with a virgin Linux. When she gave it back it was partitioned and slower than ever. I had to sign in to MS then the Linux would pop up. So not only did MS have to load so did the Linux. If it was going to overwrite the MS I wish she had told me. I ended up wiping the hard drive and reinstalling MS only.
Yeah, that was pointless.
But hey, if you're comfortable putting Windows on it, you are free! You have "nothing to lose" by installing Linux yourself! The Worst Case Scenario has already happened!
So really, get Mint, PCLinuxOS, Debian CD#1 Xfce version (otherwise it puts on Gnome by default), and go for it. Really.
He thinks youtube is retarded and a waste of time. This from someone who will watch and entire NASCAR race.
I don't mean to be impolite. That is _funny_.
Living in NC, I know lots of people like that. Funny, funny funny.
So his requirements are a few drivers, virus protection and an ISP. He not even all the fussed to have me install open office.
1) What kind of network connection does he have? If it's DSL or Cable, you've got it made in the shade. It will "just work". Dial-up, I can't help you with. It's been too long for me.
2) Drivers are all in the kernel, again don't worry unless that laptop has a Broadcomm wireless card, in which case you might have the extra step of finding the "non-free" driver. Linux-on-Laptops, LinuxQuestions.org, LXer.com, and the forums of whatever distribution you decide upon, are your friends.
3) Virus protection is not an issue for several reasons:
3.0) Nothing auto-executes.
3.1) Viruses are almost exclusively Windows binaries. Those don't run on Linux.
3.2) *NIX style user/root separation means that even if something does run, it runs as the user, not root. So the system files don't get touched.
3.3) Distributions maintain known-good repositories. This avoids the "where did you get this?" problem.
3.4) Use Gmail or some other web based mail, FireFox with NoScript and AdBlockPlus, and that should take care of it. Really. Don't bog down your system with anti-virus, since you're not running an open email server.
4) I'd still install OpenOffice.org and Flash, just because. Never know when someone will send him a MS Office document he just has to open.
And like I said already, you've already exercised the nuclear option (reformat and reinstall) on that laptop. You cannot get yourself into any worse trouble than you've already dealt with. Go ahead, try some things out. Freedom to experiment! What a wonderful feeling.