I have a HP-laptop, it had no install-media packaged so I had to make myself from Vista.

Result is 2 DVDs. Vista checked those disks after burning and those are OK.

So, when I try to open a DVD, or an ISO in location, vLite tells me "Cannot find the expected files. Make sure you select the folder or the drive, which contains the Vista installation files, usually on the installation DVD. Note you cannot use the installed.."

So what is this?

many laptos have their own formated, sometimes linux boot(like fujitsu-siemens) disks.
i don't know the exact structure but look for a folder named "sources" or for a BIG file, named "install.wim". if you can spot them somewhere there is still hope.