Pro has more networking. security, and domain type configurations available than Home. Pro can be configured to become a mini-server and maintain securities that Home cannot.
If you are a single user, there really is no need for the Average Joe to switch to Pro. If you are more technically proficient than most, you may want to go with Pro.
Yes you can install, Since you are using Home you can Upgrade to Pro or do a fresh install. Floppy not needed but CD Drive or network capabilities are. Neither one should be attempted without first reading and understanding the steps needed.
Check out
http://www.microsoft.com/windowsxp/p...de/default.asp