Using my Mac desktop as Time machine

Yesterday I used the hard disk of my mac desktop computer in target disk mode in order to create a backup of my MacBook Pro. I think this may have been a mistake, as today when starting up my desktop it looks like it is brand new and is asking if I want to restore from a back up or use disk repair facility. I had not made a back up of the desktop computer. You may ask why? I did this as my external HDD that I normally use for back up of the MacBook Pro said it was full. I was in a rush so thought I could use the available space on the desktop computer. Now I am away on holiday and have left my wife with a the desktop mac not working. She had some photo albums on the desktop which she had put a lot of time in to produce. Can I recover the desktop to how it was before I created the laptop back up? I can ditch the laptop backup if needed as it was just a precaution while I am travelling. . I am running OSX 10.7.5 on laptop, probably similar version on the desktop. Thanks very much.

 

I used TimeMachine to backup my macbook pro on to the mac desktop.

I am now home and when I start up the mac desktop in target disk mode, I can see all the user files are still there. So I'm pretty sure all the desktop should be OK. It is just that when starting the mac desktop in normal mode it won't boot up properly. I think that the desktop is getting confused and is trying to start from the backup copy of the macbook.

How can I simply delete the timemachine backup of the macbook, so that I can get back to where I was with the desktop computer before this started?

Thanks!

 

Problem solved

OK, the problem appears to have solved itself

After my last post I thought I should check exactly what the error was with the startup of the machine, so I restarted my wife's mac desktop (after having run it in TDM) and it booted up just fine. I don't know what she did or whether me creating a time machine back up of my macbook pro had anything to do with the issue she had while I was away last week. She did say that she had re-started a number of times, but who knows

It would be useful to know if I am likely to cause any problems by having a time machine backup of the macbook pro sitting on the mac desktop? This is only a temporary measure as I'm in the process of researching what to purchase as a NAS device so that I can store files that we both use on a separate external drive and create timemachine backups of both the laptop and desktops on a RAID configured NAS.

Thanks!