The best and most effective way to flash (install) a ROM (after backing up with Titanium) is:
-Dl'd the ROM of your choice (can be done in DroidForums directly - Chevy's will take you to his server to dl'd)
-Open a file manager (Astro, Androzip, etc.)
-Go to /sd/download folder and find the .zip and long press it
-Select "Move"
-Press your Back key (upper left should now say "/sd"
-Select "Move Here" (zip is now on the "root" of your SD card)
-Exit file manager app
-Since you already have ROM Manager, we'll use that to boot into Clockworkmod Recovery
-Open ROM Manager
-Select "Reboot To Recovery" or something along those lines
-When your phone boots back up, you'll see the "M" and then it should go to CW
-Using your volume keys, scroll down to "Backup/Restore" and press your camera button (enter)
-Select "Backup"
-Wait for it to finish (will take a few)
-You should be back at the main menu now
-Scroll to "Wipe data/factory reset and press camera button
-Select "Yes -- delete all user data"
-Scroll to "Wipe cache partition" and press camera button
-Scroll to "Mounts and Storage" and press your camera button
-Select "Mount /system" (should see it change to "Unmount /system"
-Hit your power button to get back to the main menu
-Scroll to "Install zip from sd card" and press your camera button
-Select "Choose zip from sdcard"
-Scroll to the zip of the ROM and select it with your camera button
-Select "Yes - Install"
-Once install is complete, hit power to get to main menu
-Select "Reboot system now"
-Your first boot WILL take a few (1-5 minutes) so don't panic. You should hear the haptic feedback "bump" (like when pressing your back button) and the boot animation will dim, indicating that all was successful.
-Reactivate your phone by following the on screen instructions and selecting option 1 on the activation call
-Sign in to your Gmail (will restore contacts, Gmail, calender, and paid apps). Sync can take a few depending on the quantity of the contents (apps, contacts, etc.)
-Enjoy your new ROM
*NOTE: Restoring your apps in just the market will NOT restore their data (progress). Restore "App+Data" in Titanium Backup for that.
If you need help with anything, don't hesitate to ask.
DroidForums Junkie!!