Can't update, do not have permissions

Question

First off, cards on table, I am the sort of lazy person who just wants to switch on my computer and start using Photoshop or my other applications, I have no real interest in the background stuff (at which point I begin to display luddite tendencies)
Recently my old imac ceased to work and, given its age, didn't bother with a repair option. I bought a new imac and asked the shop to remove the hard drive from the old one as indications were that it was OK. While waiting for this I set up the new mac as I didn't want delay in access to emails and the internet so did not use Setup Assistant. On receiving the hard drive I used Migration to transfer my stuff.
At one point in this process a message flashed up, I can't remember the exact wording, but something about not being able to transfer some items as it had an identical account name as the account on the machine I was transferring to. Without thinking of any ramifications I entered a new name and the transfer continued. Some applications appeared on my new machine in a folder assigned to this 'phoney' name but I was able to transfer and activate them using my 'real' account password.
Everything has been working well until I just tried to install an update to one application. On dragging to install I get a message stating I do not have permission to do so. Going to Get Info I discovered that read and write permissions are held by the 'phoney' name I created for migration. Further checks show this applies to some, but not all, of the applications I transferred. Looking at system preferences I see that under 'other accounts' the 'phoney' name is listed (as admin).
Am I correct in thinking that I could install the upgrade by either logging in as the 'phoney' name, or, alternatively, staying logged in as me and trashing the old version of the application before installing the upgrade. (Would this work for all other upgrades for any other applications that 'phoney' has permissions for, I've never understood if an upgrade is always a complete new clean installation or the installation of small alterations to an existing programme) If this method would work would it gradually put 'phoney' out of the system.
Finally (and apologies for this rambling post but as I stated I am in territory I don't fully understand and would prefer in an ideal world not have to bother about – same with my car oil, water and tyre pressure are about my limit of interest) ) is their a simple solution to changing all the permissions over to me and then deleting 'phoney'.
Thanks

Answer 1

If you are dragging and dropping a new application that replaces the old one, then what you can do is first delete the old version, which will require your admin password, and then drag the new version into the Applications folder.
As you say you don't understand if it is changes or full replacement, that would be really important to know right now. However, if you download the update and it is one which to drag from the install disk into Applications, then it is replacing the whole thing. My above advice should fix that case.
If the Application is modifying itself, then you'd need to change the permissions on the app.
My suggestion would be to download [BatChmod|http://www.macchampion.com/arbysoft/BatchMod/Welcome.html] and set the permissions that way. While most apps you drag and drop install get the name of the person who dropped them, you can use root:admin as the owner:group. What you want is for the owner to have read, write, execute permissions, and group and others (everyone) to have read and execute. You also want to apply to enclosed and files.
You can drag the app to the BatChmod interface and it will show you the permissions and owner. What you want to see is
owner: group: everyone
root (or your real user name) admin
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