If I do a FDR, will I have to reinstall all my apps??? Will I lose anything? Or is it basically like a reboot?
for all intents and purposes, you will lose everything. (except the SD card - that will be safe.)
it completely wipes the phone's internal memory, but afterwards, it'll automatically re-download your apps, sync your contacts, emails, etc. however, you'll have to re-set-up all the settings in your apps, ringtones, notifications, non-gmail-email-accounts, etc.
it's a pain in the rear end, but i blocked out like 2 hours the other night and just sucked it up and did it. it was totally worth it...but then again, i didn't have a choice, really. i had some serious problems with my initial upgrade to ICS.