I am planning to install the latest version of Red Hat on a desktop computer, and use it as a platform to become more up-to-date on Linux and associated open source applications. I'm thinking to buy a used Dell or HP desktop computer; maybe two or three years old (or newer); on which to install Linux. It's been several years since I've installed Linux and I was wondering if anyone in this group could recommend desktop make/models which are popular for installing and using Red Hat.
Pretty much any modern desktop or laptop with 4 of more GB of RAM is fine for running RHEL.
Official RHEL5 and RHEL6 documentation say that 512 MB and 1 GB are the minimum memory requirements for 32 and 64 bit, respectively... pretty much any computer would do.
I have some VMs running with 256 MBs though.