What do you think about Linux systems?

I'm actually thinking that if I have nothing to do this summer, I might organize all my files onto disks (my hard drive is only 80 GB, and it's the oldest part of my computer), and completely wipe this Windows installation. I'll try to figure out Linux. If it offers at least as many possibilities as Windows, then why not? But it seems like you need a lot of theoretical knowledge to manage everything... And that's probably the main reason for Linux's lack of popularity.