A couple of thing I would do first.
1. Suspect that your USB cable is suspect and try using a different one. If it is suspect, it may be loosing connection during the sync process, causing the issues.
2. Turn off automatic connections on the MacBook, so only one thing happens at a time, as this may be causing issues.
So without the iphone connected, launch iTunes and select
iTunes>Preferences>Devices.
Check the box for "Prevent iPods, iPhones and iPad from syncing automatically
Close iTunes.
Next Launch iPhoto and select
iPhoto>Prefernces>General
Change Connecting camera opens: to "No application"
Close iPhoto.
These two setting changes wil allow you to manually control all syncing.
Now with those setting changed, connect you phone, using a different cable and launch iPhoto
Import any photos that are avaliable for import.
Close iPhoto.
Launch iTunes
Select your phone on the left list and then on the right click Back Up Now selection.
This should now make a full backup of your phone.
Once the backup is cmplete, you can now select "Check for Update"
Once it has found the update, You can Download and install it.
When asked at the end of the process, if you want to restore your phone "new" (factory reset) of from /backup, select Backup and it should restore the phone from the backup you performed at the start of the process.
Sync any changes you want to make to the phone, backup it up again once the new sync is complete and disconnect the phone from itunes.
If these processors fail, you may have a hardware issue with the phone or the macbook.
A