64 Bit Linux shows 4GB... was Using all of 4GB RAM...

[Linuxguy123]

On Wed, 2008-10-01 at 13:10 -0700, Craig White wrote:
> > So... what is the easiest way to convert my 32 bit installation to 64
> > bits ?  Please don't tell me to reinstall because I just did that
> > earlier this week to go from F9 back to F8.
> ----
> sorry - reinstall is your only option

Reinstall the kernel or the whole "OS" including the applications ? 

How do I "reinstall" and get the exact same set of applications that I
currently have and keep all my user data ?

I was hoping that I could change a setting from i386 to x86_64 and some
magic would occur whereby everything got replaced.  Even if I had to
write a yum script to do it ?

Thanks.