1) I recommend to clean reinstall the OS, here is how to ( for win7)
http://www.tomshardware.com/faq/id-1856199/install-windows-ssd.html
2) You can get any SATAII or SATAIII cables, like
http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=100016766%208000%204808&IsNodeId=1&name=Free%20Shipping&ActiveSearchResult=True
3) yes, the SSD will be faster than the regular HDD.
4) More info from Kingston, there are some video for all you need to know.
http://www.kingston.com/us/ssd/v#sv300s3
5) After you done the installation, you need tweak the SSD like Useful SSD Articles - Part 2 http://www.tomshardware.com/forum/270102-32-useful-articles-part