What I mean is, Titanium won't help me install all of the apps that were on my phone, pre-root, right? So after rooting the first time, it seems as though I'd have to go through the pain of installing and configuring all of my apps manually. Or am I missing something?
Rooting only does one thing and one thing only
grant you root access to your phone. That's it. Your current ROM (standard Froyo) will still be intact, no changes, no apps lost. The only thing that will be added to your phone is the Superuser app.
After you've rooted, you can then make a Nandroid backup. In fact, after you root, I would do that first no questions asked. If you don't know how to go to recovery to do it, just do a search on AC, ask someone here, or google it. Its a very easy process once you know the steps and will save you a lot of heartache and pain.
After you've made a nandroid of stock Froyo then you can download Titanium and do your app backup.
After that, start flashing whatever ROM you want to try. Your Nandroid is there to get you back to where you started in case the ROM you choose isn't what you like or something goes wrong. Just like DINC said, when you restore your Nandroid it reverts back to the snapshot it made like nothing ever happened...all apps that were there when you made it will be there..any progress made in a game (angry birds) will be the same as when you made the back up.
It really is an easy process to flash ROM's. It only takes a bit of time to reset up all your apps and settings and with tools like Titanium, it only takes about 30-45 minutes and you're all back and running the latest and greatest. As I write this I'm using a ROM that is Gingerbread based and utilizes Sense 3.0...if I were to wait on Verizon for that sort of update I'd be waiting for the Sun to stop shining.