First try to see if it's just a blown fuse problem. I don't know how to check that with the Klipsch sets, but if that's the problem it will be very cheap to fix.
After that I think it depends on your own personal feelings.
Looking at costs:
1 Fix the Klipsch = under $150?
2 Get a New receiver and use Klipsch satellites and Klipsch sub = $175 and up probably
3 Get a Logitech set = $225-ish
4 Get a HTIB set = $300 for an Onkyo 580, about $425 for an Onkyo780
5 Put together your own HT system = $???
As far as sound quality goes, you're probably looking at
1,2 being just about exactly what it was before
3 depends a lot on who you ask. You'll probably have more bass output but it wont be as tight as the Klipsch output. Mids and Highs - personal preference, but Klipsch probably has the upper hand.
4 personal preference again - go out and listen to decide for yourself.
5 spending more money, hunting around for used products, and building up over time will allow you to get a better system hands down.
Features/Connections
1 would be the least capable giving you just the same 5.1 analog input you had before
2 would get you the same 5.1 analog input if you pick the right receiver along with a few digital inputs and several more stereo analog inputs. You would also get several more surround sound modes, DD and DTS decoding, speaker level adjustments, speaker distance calibration, etc.
3 would get you 5.1 analog, two digital connections with DD/DTS, and some surround processing options
4 would get you connection options similar to 2
5 depends on what you get and could even include equalization options etc.
Upgrade Options
1 you're stuck back at square one
2 easy option to upgrade the satellites or sub later on
3 same as 1 except the system would be better suited for use as a HT set too
4 the Onkyo receivers are good buys in these sets and are really the strongest links in the HTIB sets so they would be good to keep if you wanted to upgrade your speakers or sub later on
5 you can build up over time and leave whatever upgrade path you want to. Just getting a receiver and a pair of bookshelf speakers for now and using the Klipsch satellites for the rest of the speakers for now and the Klipsch sub would leave you with a lot of upgrade options
There are other considerations like size, longetivity, etc. I guess the point is there isn't a "right" answer to this.
I have no regrets moving away from "computer speakers" to a more HT oriented system. I'd do it again. Of course the main factor here is cost with size being the second drawback. At 46 pounds, my center channel weighs more than most computer speaker systems.
So in conclusion, try to see if it's just a fuse for the Klipsch. If not, decide what your long term goals are for your audio system and how much money you think you might want to put into it in the long run.