I use Photoshop CS5. A lot of my photojournalist friends swear by Lightroom, I haven't tried and have years of custom built actions for specific looks (like the dave hill, dear sweet jesus that is insanely overprocessed with a high pass filter & desaturated look.... or creating a skin softening layer mask) or repetitive actions (rotate canvas .1 degrees, interpolating photos, etc) that I use a lot.
Photoshop elements or Lightroom is more than the average photographer on vacation or someone who photographs their kids would ever need. At most you'd be adjusting the levels, adding a little contrast, straightening the horizon, little basic adjustments. Most people arent doing what Alan is doing and removing trash cans or Prince Charming's Cable hookup. (Zip line? What is this "zip line"... TinkerBell flies, really!) Most are not going into selective color and poping the reds.
Also I am a big believer in shooting it right the first time, doing most of my tricks in-camera and throwing things at people who say "oh you can fix it in post" and rarely shooting in RAW. Jpeg large, for those wondering (RAW takes up too much space for my likings and I really hate converting it) unless the client specifically asks for it. (Please don't start a RAW debate, I'll simply show you negatives from my Holga while you type)
My workflow also involves ingesting the photos using Photo Mechanic with a boilerplate caption, time, date, place and basic keywords for archival purposes... ala "the Magic Kingdom at the Walt Disney World Resort on Sunday, December 16, 2012 in Lake Buena Vista, Fla." If you shoot a ton of photos, you want to do as much of the archival organization on the front end. (Nothing like trying to find a caption for a photo 15 minutes before a contest deadline)
Also .... as much as I hate the "green box mode" on modern DSLRs, they give beginners nice exposures. Otherwise, sunny f/16s always applies. (In bright sunlight, your exposure is 1/ISO at f/16)
Back to Steve's observation. You shouldn't need a new computer if its something you've bought in the past 3-5 years but you may need to expand the RAM in the computer and also be aware of what other programs are running in the background. (iTunes is a notorious resource hog as well as most Adobe programs) Short troubleshooting suggestion says to restart the computer, only run the RAW converter and see if it still is acting up. From there, defrag your hard drive if you're still having problems and try to remove any junk applications you'd have running.
Alas if money is no problem here, yes, drop 5 grand on a new mac tower, load out the RAM, get an insane display and the latest version of Photoshop.
Nothing worse then forgetting to restart the computer and photoshop takes forever when you have a 10 minute window to download, edit, caption and file 3 photos from the first half of XXXX sporting event.