Upgrade 2.1 to 2.2 with apps?

[Guest Kiwizz]

If I backup everything using titanium backup, then flash my phone with the new froyo rom, will I be able to restore them and their settings?

I am asking because I have a feeling some apps will not be compatible with 2.2.

Also, I have apps2sd installed, if I flash a froyo rom with apps2sd, will it be fine to leave the sd card as it is - already apps will appear? Or should I format the ext partition and then restore the apps via titanium backup?

Thanks!