IPhone 4 has to be restored every time I want to sync + Other ridiculous problems

Question

Hey,
I am on a Windows 7 (64x Ultimate edition) machine, and I own an iPhone 4 16gb, and pretty much 75% of the time I plug my iPhone in to sync it, it will get to syncing the files (whatever they may be, regardless if there are any new updates or nothing at all) and then it will say:
The iPhone cannot be synced. A duplicate file name was specified.
After this, i must restore my iPhone. From here, I then click on the latest backup and click restore. This is where it gets stupidly ridiculous.
The progress bar for the restoration won't move unless I click and drag the little restore box around my screen. It's as if the computer doesn't realise it's meant to be doing anything unless i'm physically dragging and dropping the window all over my screen. What the computer estimates to take about 3 minutes (I have never had it work propperly so i don't know how long it usually takes) will take me about 20 minutes of me dragging and dropping.
THIS IS THE MOST ANNOYING THING I HAVE EVER EXPERIENCED.
Once it is finished, it will disconnect for 10 seconds, reconnect and be fine. then i can backup the phone and sync etc. Sometimes when i connect to the computer it is fine and backs up and syncs fine, but the majority of the time it screws up (always in the same way) and i have to go through the process again.
If anyone could PLEASE shed any light on how i can fix this, it would be unbelievably appreciated, i've dealt with this problem for about 8 months hoping with each iTunes update that it would be fixed but alas it has not.
Other info regarding iTunes:
I have two internal harddrives, C: and D:.
D: was my original harddrive (320gb so when i upgraded computers i moved it into my new one as a slave to a 1tb harddrive. I still keep all my iTunes stuff on my D: drive and have iTunes installed on C:.
My music on my phone is manually managed so no, it doesn't sync music when it plugs in; it only syncs new apps (+updates) and new photos.
If you require any additional system information then i am willing to post.

Answer 1

It's not a matter of me assuming to restore it, once the error comes up, the only next step I can do is to restore it. I can't access any of the iphones settings in itunes or anything, it's a mandatory restore. If I just cancel the sync (before restoring) and disconnect the phone, all my apps crash on opening: aka unusable phone. So I have literally no choice but to restore every time the error shows up if I want my phone to work.
I have no idea where I may have duplicate files as it doesn't tell me, so if that is the problem (which I don't think it is) then I don't know where I have to go to delete the duplicates.
And the duplicate file error still doesn't explain why leaving iTunes to restore the phone doesn't work and me having to drag the window around. I know it sounds utterly ridiculous, my friend didn't believe me when I told him either but then I showed him and he was as confused as I am. If I just leave the restore to do its own thing at it's own pace, it will loa maybe 20% then fail for whatever reason.