Gaming on PC will be history before Linux will be ready for it..
Very true, not that linux isn't ready for it - everybody makes games with dx (opengl ftw, i love standard things - which is why i hate ms - sorry i'm nuts) now and everybody uses windows or mac now so there's really no point - linux is only common in production servers, only over the past few years growing in popularity for desktop users.
When I started trying out Ubuntu I was pleasantly surprised at how much stuff I managed to get working. But for me it takes more effort to get the stuff to work on Ubuntu than on Windows. I've installed Ubuntu a few times on different computers and some really basic stuff such as Flash has always been a pain to configure. Sometimes it works right away, but after some minor software update Youtube might stop working and then I have to install some beta plug-ins or whatever. When I upgraded to version 9.10 the sound in DosBox went really f***d up without any obvious reason. On Ubuntu it's totally useless to try mixing some songs on Audacity because the sound starts distorting when it really shouldn't. Minor but annoying things such as these force me to think Linux just isn't quite "ready" as a desktop OS yet. In the long run I consider the open-source OS's to be the only way to go but I'll use Windows until developers (game developers too -- current "Linux gaming" is just a joke even though Ur-Quan Masters has a port) take desktop Linux more seriously.
Ubuntu sucks, but linux is a more than suitable desktop operating system, if you don't game (but some games can be run in wine, or if you has the ramz a vm could be setup) - surprised about the flash problems, flash takes no configuring at all, especially since the 64bit version came out if you're on x86_64 --- again, I blame ubuntu for your flash problems.
Basically, all of your problems, except for the lack of games, are ubuntu's fault - use debian or something else good before you judge linux as a desktop (and upgrade to zen kernel - best for desktops
). Contrary to popular belief, things break in ubuntu, unlike in debian (debian's old but if you use testing it's rolling, up to date, and generally stable) Breaking in debian is a lot more rare if you don't do dangerous things - every ubuntu release upgrade seems to break - and gnome is the worst, especially ubuntu's implementation of it.
My linux recommendations - just preference, osol is a possibility too:
1. Debian
2. Arch (takes much longer to configure) - but chakra is an option for an easy awesome kde arch
3. Fedora (just as easy as ubuntu, has annoyances of redhat and is more annoying to do custom things but sucks less than ubuntu)
4. Yoper (rpm-based, but uses better alternative for package management - and I talk to the main developer all the time)
5. Gentoo (don't use gentoo, i just dont like anything else enough to give it #5)
Way further down: Ubuntu/Xubuntu
Even further: Kubuntu