Kernal panic after installing LR3- now after re-install,no privileges

Question

imac
2.4 gHz
300 HDD
3G ram
I installed Lightroom 3 and in 64 bit mode it crashed the system with 'kernal panic'.
Managed to get it working in 32 bit (slowly) but was advised to re-install 10.5.8 as I was getting ACL found but not expected errors when I tried to repair permissions.
I re-installed but now find I have no administrator privileges - so can't do any updates etc;
managed to do: Installer>Utilities>reset password - but it still says password is wrong.
I also had used Time Machine to back up my system : when I tried to restore, the restore button is greyed out - I can select on various items, but that is as far as I can get.
Am at my wits end - don't see why the re-install has caused this problem

Answer 1

If all else fails, you can reinstall Snow Leopard using the same installer disc you used to install it originally (or your grey system discs if your Mac came with Snow Leopard installed). This will not erase your user files but you will have to update the OS & Apple-supplied apps after the installation. This isn't as painful as it sounds if you use the Software Update app immediately following the first normal restart after the installation completes. Software Update is smart enough to pick the most appropriate update(s) to get your Mac back to the latest software, including automatically picking the Combo version of the OS updater if the installed version is more than one minor version behind the latest one.
In fact, given how slow a Time Machine restore can be, if you have a fast high speed Internet connection this could take less time & effort on your part than doing the TM restore. Plus, it guarantees that you get the latest versions of everything & that they are all properly linked.