Hard drive backup Question

[trotski]

I want to install Window XP Pro Corporate edition, but my comp won't let me (says it's an older version that what is on my comp already, which is Win XP Home SP2). So, I guess I will have to do a 'clean' install.

My question is, can i backup my entire C: onto an external hard drive, and save all my programs, and then just transfer them all over after I do the clean install? And if so, are there any good free backup programs out there or is Norton Ghost better for that?