Nothing wrong with Vista at all, so long as you have it updated. Whoever says otherwise, is talking through their arse; it was dodgy upon release, for a number of reasons, but Microsoft addressed most of the criticisms.
7 is also fine, but personally I prefer Vista in a few area's, though as my newest laptop shipped with 7, I've tweaked it to look and feel more like Vista, and just continue to run 7.
Back to the original question, can you confirm the manufacturer and model number of the laptop please? Also, it's worth making a note of the COA key (Windows Serial number) and Vista version which is usually on a sticker on the bottom of the machine as these tend to wear and become unreadable (if it hasn't already). This way, even without a recovery disc, you can restore Windows with a generic Vista CD of the same version and re-activate it without hassle through Microsoft, giving you a fully legal system.
