Boom means you get basic functions for basic hardware. It's the middle of the road, high and dry and useful. You usually get internet access if you have a service or DSL like I do. You get applications like a web browser, music player, picture viewer, document writer or the Open Office suite and the GIMP (picture editor). So you have to see what's included. Of course if you install it, you have access to a very large online catalog of applications, so you can add and remove to your hearts content.
Flash-boom depends on the hardware you got. You must have enough system memory or the flash will slow down the boom. I have 512MB in my laptop. I can flash ok but the boom suffers a lot. 1 or 2 gig of system memory allows lots of flash and lots of boom. The next thing is the video chips. Usually ATX desktops don't have a problem as you can swap in a new video card at will. Laptops have to deal with what they have. In any case if there are enhanced video drivers for your chip set, you are prompted to install them. The better drivers allow the flash to be big.
The next part of the flash is selecting the configuration to make the pyrotechnics work. In Linux this is called compositing. Compositing has come a long way. You can get windows that wobble when you move then, windows on a spinning cube, all kinds of fade effects, and combinations of eyecandy that will rot your retinas. I have turned them off on my laptop so it remains snappy. On my desktop I kept just the drop shadows for that 3D look.
Other add-on features are icon bars that rival Apple's Mac and side panels that mimic dashboards. Some features are only available on certain Linux desktops. The Gnome desktop is one way and KDE is another and XFCE (on my laptop) is another. They are mostly the same but have different user strategies, different styles, different looks and different features. Same but different.
It all sounds hard to do but that's because most don't know this stuff until they've messed with it a little while. So find a Linux user group, Linux savvy PC shop, or something already! There are lots of advice givers on the net, forums, videos and such and me. I'm no expert, just a humble guide with some experience. My forte is the desktop not servers. I think the Linux desktop needs more support so that users have help on their own level. I hope you find Linux of any flavor a restful retreat and a reprieve from the other setups.