Gentoo, because:
- It has thorough documentation.
- It's super-easy (if a little bit time-consuming) to install software.
- It's low-level enough that I can tweak if I want to.
It compares most favorably to other distros I've used:
- Mandrake (8.1) was easy to get going at first, but quickly descended into impossibility; too many RPM hassles, and I ended up needing to install a lot of things from source.
- Debian (3.0) was an installation nightmare on every machine I tried it on. I have a 6-CD set, but for whatever reason the installer couldn't read the CD-ROM soon after booting and configuring; I only succeeded with installation by pulling everything over the internet.
- Slackware (9.0) I installed once on an ancient laptop. This would be my second choice after Gentoo; I found it hard to get ahold of ISO images, which is the only problem I had with Slack.
Others that I'd use for certain purposes:
- Knoppix, for when my wife gets bored of Windows-only on her box.
- Damn Samll Linux and/or Vector Linux, to have more streamlined Knoppices for old machines.
- muLinux and SmallLinux for getting started on even older machines.
As for how much Gentoo suits me, I'd say not as much as an ideal distro might. To me, the ideal Linux distro would:
- Detect and configure all hardware without intervention. Knoppix comes closest here; it does not detect/configure my Ethernet card on any of the three boxes I've tried it on, and had video detection troubles for one of them, but aside from that it's great.
- Require less intervention for hard drive partitioning. Mandrake was fairly good on this point; obviously a tricky issue if an OS is already installed, but I wish more distros made this potentially dangerous and confusing task easier.
- Detect existing storage devices. I shouldn't have to read, understand, and edit /etc/fstab just to use a floppy disk or burn a CD-R. Most distros I've used seem to handle this poorly. Gentoo was the only one that used my flash memory stick without any intervention, but lots of fstab editing was required to get Gentoo installed.
- Have a GUI for everything, just in case (this alone would make Linux much easier for the general populace, IMHO - if they are well-designed GUIs, something which is shamefully rare.
Of course, most of these don't matter so much after everything is configured, and aren't as important to someone who is comfortable with the command-line, but sometimes I just wanna click the mouse instead of reading manual pages to remember the syntax for 'find' or 'emerge', or what modules I gotta load to get my USB printer to work, or, worst of all, remember where the damn manual for my monitor is so I can find out the refresh rates, edit XF86Config and get some decent resolution.
System specs of all the machines I've run Linux on at some time:
Athlon XP 1600, 512 SDRAM, 80GB HD, Mandrake 8.1, now Gentoo (my main box)
Athlon XP 2100, 512 DDRAM, 80GB HD, Gentoo (my wife's currently Windows-only box)
K6-2/350, 128 SDRAM, 13GB HD, Debian 3.0/Windows98 (gave to my aunt)
K6-2/300, 768 SDRAM, 13GB HD, Debian 3.0 (once a firewall, now stripped in closet)
K6-2/266, 64 SDRAM, 8GB HD, Vector (traded for box I gave to aunt, gathers dust)
486 DX2/66 Laptop, 16 SDRAM, muLinux (screen and floppy dead)
486 DX2/66 Laptop, 4 SDRAM, 200MB HD, Slackware 9.0 (currently serving as a cat perch)