to answer your original question, you should be safe when you sync your iphone.
coming to your second problem, if you have a huge .pst file then expect outlook to take a long time to fix it...in the meantime your comp. may become unresponsive.
if you cannot copy your .pst file then try using the safemode with or without command prompt.alternatively google unlocker 1.8.5 and try using it.
if your pst is still unrecoverable then use a third party software like Kernel-PST-Demo. i used it once to search for an email id that i had lost when my pst got corrupted, i don't know if the demo will allow you to salvage your pst but it surely will allow you to open the pst and maybe save a few imp. email id's

what's command prompt? please dont laugh too hard, i'm serious
I have tried loading windows into safe mode AND outlook in safe mode, stil stalls the computer. Kernel-PST-Demo looked like it would work, then another stall. Its like whenever i touch this pst file or try to open, even copy it, it affects my computer. I left the computer running and ran outlook while i slept to see if all those hours would fix the problem. Nothing. this blows.

im not sure. that happened to my dads windows mobile phone, with outlook so i cant say for sure. you probably dont have the equiptment, but u could always connect ur hardrive to ur friends computer externally and then copy the file over. but this is only iff u really need those emails

you said that you were able to copy the file to ur desktop, the comp froze but you sed all the bytes did transfer over(complete copy). try to do that with the flash drive, even if it does freeze, just let it copy and then ttake out the drive like an hour later.

tried to, then copied the scanpost.exe (sp) like you said but when i went to another computer and tried to run the program, I got an error. I think I need other components to run scanpost