At the moment one of my websites ranks 2nd on a keyword, if I redesign the website, will the place be lost? Should I just keep the meta keywords or description?
there will be temporary fluctuations in the ranking. be sure to apply 301 redirect on the pages if you change the URL also. if you are changing only the design then there won't be any rank droppings
If you radically change a website, especially if you change the content and overall structure, it may hurt your rankings. If it's just the design, it depends on how much this change affects the structure of the individual page. As Shailendra said, this negative effect on rankings is just temporary. I'd keep the metatags, the less change, the less risk.
Yes, it may reflect few changes. You must have to do on-page optimization well to doesn't drop your keyword position also have to maintain the keyword density in your content. All the best...
It can effect your rankings... for the better or for the worse... If none of your URLs change and it's just a facelift, typically rankings won't change much if any. But if you are changing URLs then you MUST 301 redirect the old to the new URLs... and while the search engines recrawl all of the links to the old URLs to discover the 301s you WILL see a drop in rankings and a drop in traffic. But it should come back in a month or two depending on how often they crawl the sites that link to you. Also if are changing things like <title>, <h1>, <h2>s, content of the page, link text for pages interlinking, etc. then expect some changes. Don't be afraid... just do LOTS of planning. Here is a post I made a few months back. I think it has a lot of useful tips in it on things you should consider from an SEO perspective for a site redesign.