If you want lightweight... What about
Tiny Core?
It's the most minimalistic functional GUI desktop you will ever find.
Also
Ubuntu's interface just doesn't go along with me. You know you're in a bit of a bind when your interface just doesn't work. Mixing Windows 7 and OS X is probably one of the worst things that you can do. :P
GNOME 2 was made before OSX or Windows 7. :V
That is what it was based off of. And you can make GNOME look like almost anything. No need to keep the default if you dislike it. :P
And Linux Mint used to be pretty much GNOME 2 Ubuntu with a new Mint Menu, not anymore.
Recently, Ubuntu changed to an interface called "Unity"... I personally don't like it, but it is the lesser of the evils when you compare it to Metro and GNOME 3 Shell. Linux Mint on the other hand, recently modified the crap out of GNOME 3 so that it was still the newer API and it acts a lot more like what most Linux users are used to. It is also quite infamous for setting everything up for you. It's interface is much more Windows-like by default than most distributions.
I think it must be some sort of rare hardware combination that I have that's causing problems with these Linux distributions.
openSUSE seems to be out for me, too. Again, stability problems... during install. Strange...
This doesn't surprise me, Red-hat based distributions like Fedora and OpenSUSE tend to work like Red Hat Enterprise Linux beta, an unstable version of it... It is it's testing phase before new releases of RHEL.
If you are going for stability, I would highly recommend a Debian-based distribution unless you are looking to do a lot of stuff from the command line. (And if you don't mind that, go for Slackware or Gentoo..! But be warned, they are brutal. But I love em anyway.)
Any Linux can be made into whatever you make of it... The kernel may have been modified some, but the base system is modular and interchangeable. With enough work, you could convert Arch Linux into Mint, or Fedora into Gentoo. Everything is editable. The main difference between the distributions is it's default settings, default desktop environment, and the package manager. (Debian-based uses dpkg and apt, RHEL-based uses rpm and yum, Arch uses pkgbuild and pacman, etc...)
Just note that Linux is not really for everyone. I like it because I am more efficient at doing things in it, plus it can do cool things that I can't do elsewhere. But if you are forcing yourself to try it and wish to stick to Mac or Windows, then stick with Mac or Windows. :)