Sorry I didn't reply again quickly, UFO: AI is a spare time project and I got very busy for a few days...
For starters, if you haven't already tried it you may want to check out
64Studio:
http://www.64studio.com/They have both "Live" and "Install" ISOs you can download, all of it free.
Regarding Kdenlive, The latest version is much more advanced and full-featured compared to the previous time I tried it, and it now looks like it already rivals some of the less expensive commercial non-linear editing suites. On my computer it runs quite well, although I didn't test it extensively.
If you multiboot Windows, a program called
VirtualDub is a must, especially after downloading some extra codecs and choosing from the many plugins on the net that people create for it. VirtualDub is on Sourceforge.
Another video app, cross-platform, that I'd like to mention is
OpenVIP - also on Sourceforge, but I don't recommend it because it kinda fizzled out in development and didn't get very far.
For Linux,
Lives is another video editor you could also try:
http://lives.sourceforge.net/Blender also has a video-editing mode, similar to various non-linear multi-track video apps, in addition to the modeling mode that comes up by default.
For Music/Audio:
This is a different story - it depends on what type of music you want to make. I've been making music for years on computers, since the 1980s on an old Commodore 64 with various C64 programs, long before any of the modern DAWs were around and available to typical home computer owners. I remember those days, when being lucky enough to get "studio time" really meant something and wasn't a joke like it is today, because if you didn't have millions to blow on a pro studio your music demos would sound terrible and amateur compared to a commercial track from a signed band. It wasn't like today, where people now can make pro-sounding recordings at home in a bedroom or get close to it.
I've looked at the free programs for Linux, and unless you stick strictly to electronic-sounding tracks and aren't bothered if you don't have real or real-sounding instruments in the mix, the Linux DAW scene has some catching-up to do with the commercial setups for PC and Mac. Yes, Linux can do some of that, but not anywhere near compared to the pro commercial setups, which are
not free.
REAPER is a very good DAW that is much less expensive than others, I've even seen some ex-Pro Tools users switch to REAPER. (Myself, I'm actually a convert from using Cakewalk products before REAPER took off.)
http://www.reaper.fm/Myself I also use hardware FX processors, (real) tube overdrive and amps and such now, and real guitars on some of my tracks, usually one of my Gibson Explorers for my newer stuff (which I'm still working on, I haven't uploaded any of the new stuff with recent gear anywhere, in this forum or elsewhere, yet).
Yes, some people have luck making some styles of music with RoseGarden, Ardour, etc, it depends on what type of music you want to make.
Traverso is an open-source DAW, but barely developed, I don't recommend it.
If you're on Windows, there are *tons* of free VST plug-ins on the net, although most are crap. Some are pretty good though. (Please don't ask for a complete list, there are waaaaaaaayyy too many.)
Making and recording music on computers takes lots of work and skill, there really aren't any "Wizards" out there for any DAWs that let a new-comer to the field come and point the mouse, click the buttons for a few quick minutes, and then almost instantly end up with a fully-mastered and pro-sounding music track. It really takes
years of work and discipline, in fact. Even the guys I've seen who get college degrees in computer-based music and sound stuff have already had extensive experience in such areas even before they start their degree programs, already having strong musical backgrounds.
Hope this is helpful, and BTW it is past midnight where I am right now, so I'm sorry if any of it is hard to read...