The Epson R3000 printer is more efficient with ink than the older 2880, also it is built better. I've owned both. The ink is a huge rip-off so I'd weigh how many prints you really expect to make... if you do less than ~50/year it is upside down. The Harrington Quadtone RIP works with either for better B&W prints than the Epson driver. For color you want to print from Photoshop with the print driver "off".
For someone not overly computer-savvy just get the largest Apple iMac with the most amount of RAM and hard drive space you can afford. I use a Mac Mini set-up myself, if you get yourself a decent display like the NEC P221W then it can be somewhat less expensive, but for simplicities sake it is hard to beat the iMac platform. iMacs are fairly well built compared to similarly specified off the shelf PCs. You also have far better security from Viruses and such, although you still need to monitor what is going on in the eco-system and have the horse sense not to download/launch/install anything you aren't 100% sure of. Most likely PC zealots will claim Macs are over-priced and they do come at a premium, but not by such a large factor as they exaggerate. For most users the advantages of the Mac OS will likely save many hours of headaches... the rare glitches on a Mac usually are solved with a restart.
Ideally you also get something like a Spyder 4 display calibrator, the basic model will do. You do not absolutely need this but it definitely helps especially if you share or sell your images with other people, use outside printers, etc.
http://buyersguide.macrumors.com lists the current models and when updates are expected so that you can make intelligent buying decisions... i.e. not pay full retail for a version on the cusp of a price reduction or update. I wouldn't hesitate to buy an Apple refurb from a respectable dealer.
In general, your upgrade money is best spent on RAM first, and usually RAM purchased from a reliable third party vendor is a much better deal than buying it from Apple. There is a push to sell you the solid state hard drives that are faster and more expensive (and reliable) than traditional drives, but I would opt for more RAM first and foremost, 16 gb minimum for larger scans.
I'd also budget for some sort of external back up hard drive solution and a small Wacom tablet. If you scan 4x5 on the Epson 700 then figure each base scan is 500 gb, space adds up quickly, it is not unusual to consume 1 tb per year if you are an active shooter.
Adobe's cloud-based Photoshop for $9.99/month has been controversial but having used it for a couple of months now, it works really well and now that Lightroom is bundled and the price is stable, I'm happy with it. The one future-proof thing I do is to save my master files as .TF rather than .PSD just on the chance that I may use some other app sometime in the future.
It's also a good time to determine a long term storage, back-up, and naming convention for your files.
