I would say it is worth knowing a bit about Linux if you plan to get on with computers -- it runs on most things and is very popular for servers. The learning curve varies from distro to distro but for the entry level it is not so bad, likewise I might not start out with debian*. Most of the headaches come with trying to get odd hardware combos working, typically inbuilt webcams, certain printers and wireless cards though all of that is far better than it was a few years back. Also for a laptop that old the wireless is probably junk anyway and they have very nice compact USB wireless cards these days (many people playing with raspberry pis use them so they are guaranteed to work on X86 linux), if you have used a compact bluetooth before then same size.
That said if you find yourself messing around with the command line these days and not just clicking on a few things you have picked the wrong distro, or it because you want to.
*it is nice and it is the thing that the easy to use distros like Ubuntu and Linux Mint base themselves on, however it is left a bit rough around the edges which works for me as I find the other two a tiny bit inclined to hold my hand on occasions (I actually use linux mint on my main machine now and have several clients on it).
http://distrowatch.com/dwres.php?resource=major has a list of most of the popular distros of Linux, stay away from arch linux for now as it is one of the more complex ones and you do not need that headache. There are some aimed very much at people coming from Windows and will make it look somewhat like XP (
http://www.zorin-os.com/images/screenshots/ZorinApps.png ) but I am in favour of the "rip the bandage off" approach.
Frankly though if you download and burn a liveCD, run that and see how it works you will have done most of the hard work (and also find out if your wireless or graphics is going to be a pain). The only real difference is Linux tends to favour using repositories to get software -- it varies from distro to distro how they set about it but if you are used to the likes of the app store/google play (by the way Android is technically a type of linux but it is a distant relation) on phones/tablets then same idea, except the software is usually free and actually suitable for use by someone that wants to get something done.
There is more but I will not pile it on at this point.
If your main machine has some power to it (dual core and 4 gigs of RAM will do) you could also try virtual machines to see if you can get on with Linux. Being a virtual machine means you tend not to face hardware issues either.