Ubuntu Hardy Heron is Unstable

I've been running Hardy now for quite a while, and I've come to the conclusion that it isn't stable. I will probably be downgrading to Gutsy very soon, however much I dislike the idea of doing so. To me, downgrading doesn't feel like I'm being part of the solution, but rather that I'm just bypassing the problem.

Here are the things I've been having problems with so far in Hardy. And, for the record, I've tried all of these things with compiz disabled as well, with no improvement:

1. On occasion (sometimes as frequently as once an hour), gnome-terminal will open with a blank (frozen, not invisible) window, there will be a grey bar where the menus should be, and I have to terminate the process. I've tried waiting it just stays there blank. Once this happens, nautilus, gedit, and even some of the file-related dialog boxes, and possibly the pop-down calendar from the gnome panel all crash in the same way, creating a blank box, and in the case of anything associated with the gnome panel, freezing the panel entirely. Restarting GDM doesn't help. I've tried everything. There seems to be nothing logged showing that there was any problem. Rebooting is the only solution.
2. Firefox 3. Not only is it annoying (due to AwesomeBar), but it feels less polished than Firefox 2. My Firefox 2 did crash every once in a while. I finally decided to reinstall Firefox 2, and give it a try. Firefox 3 unfortunately did things to the configuration which makes Firefox 2 suck as well, since it tries to run off of the same settings. I deleted the extensions.rdf file and start FF2 and everything seems almost OK. But, if I ever run FF3 again, it ruins FF2 (removes all extensions, mostly.) This means I cannot ease into FF3 while still using FF2 for my day to day work. I will thus be uninstalling FF3.
3. Random lock-ups. I haven't had this problem as much as some people have been reporting, but I have had some unusual lock-ups. One of them involved my screen suddenly appearing scrunched left-to-right and streched up-and-down with big black bars on either side and everything completely frozen (including the mouse pointer) requiring a hard reset.
4. Thunderbird is barely usable. I use Thunderbird with an IMAP account. Previously, it has worked like a charm, but now all of a sudden, it routinely crashes without an explanation. It seems to crash in two different ways. The first way will be, while checking my inbox, new messages will appear, but the program is still catching up (not usable yet), and all of a sudden the entire program will just disappear. Messages, and the main window, poof, they're gone. No word as to why. This happens about 1 in 5 times that I open Thunderbird. The other one happens about 3 out of 5 times that I open thunderbird, and it involves clicking on my Inbox and the program immediately going comatose. When compiz is on, the window dims to a dark gray to show me that the program isn't responding, and no matter how long I wait, it never wakes back up. I have to kill the process (or click the X and force quit it) in order to try again. Yes, that adds up to 4 out of 5 tries that Thunderbird doesn't work. Every once in a while I am lucky and it will work, in which case it is usually stable for the entire session until I close it.

I'm a web developer. Browsing the web, using SSH through a terminal, and checking my email are nearly all that I do on my computer, and Hardy Heron isn't ready for ANY of those tasks. Gutsy Gibbon worked perfectly with all of them. I will probably be moving back to gutsy, but I'm afraid of what a downgrade might involve as far as my user configuration files are concerned. I guess I will be making backups before downgrading.