dave1969, Hello & to the Linux section of BC Forums!
You've came to the right place for assistance, and are happy to have you here.
As to your system, most any computer built for XP can run some type of Linux OS, and while some are more familiar with Puppy than others (I'm really not), Xfce versions of Linux are also of worthy consideration. The reason why is that most of these type of distros has no bloat, doesn't require the fastest nor boatloads of RAM to run on, and can run on older CPU's. Though in some cases, the forcepae install may be needed for install. Both Linux Mint & Ubuntu has Xfce OS's of this type, Linux Mint calls theirs the Xfce version & Ubuntu (or Canonical's) version is Xubuntu. Both are good choices, can be burned to a DVD or make a bootable Flash drive, and tested w/out installing the OS.
This is called 'LIve mode', and you can see if the distro can run on your hardware, ensure that graphics, audio & network access is OK. It also allows you to try one out & choose the version you like the best. As far as one of the questions you ask, regarding drivers, this is precisely why it's recommended to be connected to the Internet during install, normally after install & reboot, your computer just works. Though it's likely that you may have to make minor adjustments to make things suit your needs, for example, some doesn't want their screensaver to lock the computer after 5 minutes, and being that you have 512MB of RAM, need to choose a blank screensaver.
In regards to browsers, Firefox is the default for many distros, including the two I mentioned above. It's very important that you do not install a lot of extensions (add-ons) to the browser. Maybe NoScript & Adblock Plus for security & adblocking & leave the rest alone. Browsers requires RAM, and you don't want it to use half of what you have. Otherwise, as far as email goes, you can view this through the browser, or if wanting to import a Mail program, this task needs do be done before installing on your Linux distro.
Many uses the Thunderbird email client, that's why this has to be setup beforehand. As far as extras goes, the full fledged Linux versions, such as Linux Mint MATE/Cinnamon/KDE or Ubuntu/Kubuntu, these comes with a lot of software pre-installed & ready to go. Though this would require an upgrade to 1GB RAM for best results. Most of these will run on your computer as is, but will be so slow that you'll be discouraged, exactly what I don't want to see & why I suggest an Xfce version, where you can add what you need. Plus these also comes with software included, just not as much as the full fledged versions.
To sum it up, you have options, though they're limited. However, you can still find a quality distro with that amount of RAM. If it'll run a very bloated XP, there's Linux options for you. With a RAM upgrade, even more.
One thing that I'd like to remind you of, there's no such thing as a 'dumb' question in this Linux forum. Your concerns are ours, and though you may have to wait a few hours for an answer, rest assured, someone will do their best to address any questions you have. Another is that each & every one of us were where you are at this very point, with lots of concerns, some even skeptical of Linux. I know that I was, as the first time I tried it, used the WUBI installer & with a cleaning app (don't use 'cleaners' on a Linux OS), wiped out the XP bootloader, and though I was able to boot into a Ubuntu install that was running inside of XP, has no access to XP. I didn't know back then what I do now, would have fixed this with a partition tool.
These type of things comes from experience, the more you run the OS, the more you'll learn & want to learn more. Linux is also very secure, though you don't need to purchase anything for it's robust security. Linux OS's also are enjoyable ones to run & learn. If you figure in all of the maintenance needed to upkeep Windows, which you don't have to on LInux, you'll find the needed time to learn. Most Linux OS's are self-maintaining, other than backups, you'll have to do very little.
Good Luck with your Linux journey, as you'll likely need to try more than one OS before settling on a final one, and we'll do our part to help all that we can.