There are quite a few factors to consider, but here are some guidelines to help you:
6) How many domains do I have pointing to the site (parked domains)
7) Do I need a site that needs multiple web sites, or is it just one site for one account (addon domains)
8) What operating system do I need, IDS Hosting uses Linux.
With the above information go to this page and work out the best package required.
NOTE: Its best to find the package that fits best then take the one bigger for room to grow, backups etc.
Remember if you want to back up your site via the full cPanel backup using FTP to another site to keep a