Question: My boss asked me to setup a secured area online, which will contain all the FTP, MySQL etc details related to our web products. This online area must be secured and will only be accessible by the user we define.

It should be easy to understand and should have functionality to download details in PDF or in word format etc.

And should be able to handle following type of scenario:
A client has 10 websites so we'll need to store FTP, MYSQL etc details related to 10 websites, so CMS should be able to accept and present the data in easy way.

Do anyone has any suggestions for me to handle such kind scenario.

Please help. Thanks!

Answer: 
You can use all three tools without penalty or issue. There's absolutely no reason for a search engine to levy a penalty on a website that uses tools that has no direct effect on the website itself (i.e. these tools aren't altering your code or using "techniques" to manipulate the search results). These tools are just informative. Nothing nefarious about them.
Not only can you, but it's my opinion that you should. Each of them offer their own variation of information. The biggest benefit is you'll be aware of any problems with a particular search engine by using all three (i.e. maybe Bing encounters an error crawling your website, but Y! & GG don't).
The exception being that Yahoo! has switched to Bing search results, but their crawler is still chugging along.