Hi nappy, Ive worked in Marketing for over 15 years now so hopefully can help here. Ive had a look at their website and the ads you linked to. I would say this company specialises in offering sales and service advisors for other companies. Normally with this type of company this is telephone / call centre based, although it looks like they also offer a face to face sales capability which I'm guessing would either be door to door or at locations like shopping centres etc dependent on the client / brief etc.
So, for instance if the client was lovefilm you might either be answering questions from existing customers about their accounts, subscriptions etc or you might be trying to sell or upsell them a monthly package of services.
The first ad was much more service based - they'll be looking (for instance) to see if you are personable and outgoing and can problem solve and stay calm (and would have a good telephone manner). As well as the usual things like can you work as part of a team etc.
The 2nd one is much more sales - for this they'll be looking to see if you either can currently, or have the skills to be trained to sell, potentially from cold leads. Skills they'll be looking for here (aside from any previous experience you may have) are assertiveness (but not aggression), persistence, resilience, and the ability to find out peoples needs and craft whatever you are selling to match them quickly. Oh, and the achievement vs targets they mentioned.
Re your 'goals' question. You can always say something like 'I know that I really enjoy working with people, so I'm really looking for a first opportunity to demonstrate what I can offer to a company and progress from there. My ultimate goal is to find a job I love doing and that I find rewarding.'
I would also make sure you can talk through your CV well, make sure you can expain why you liked certain roles (especially where its relevant to the jobs advertised) Eg 'I loved working behind the bar because i really enjoy meeting people as and giving customers a good experience' and also make sure you can explain in a positive light why you may have moved on from jobs.
Dont panic about 'leadership qualities' it's more likely to be 'drive' they're looking for - especially for sales roles. If you have any examples of starting something from scratch, being an integral team player in a project, even something like setting yourself a weight loss goal and having the determination to achieve it all give them a picture of what you are like as a person.
A 15 minute interview will literally be a 'does your face fit, do you have the right skills' so make sure you sell yourself as much as you can, be confident, look smart (I know, but you'd be amazed) and make them think that this job is the only one you have ever wanted and you've gone to a lot of effort to get it.
Hope that helps ....apologies for war and peace!