Either Colorado Springs and Denver would be fine depending on what kind of work you will be looking for. Although they are both pretty much identical in terms of available careers.
Colorado Springs now is the booming high-tech city in Colorado and has seen many new high-tech companies including Intel which expanded there campus recently also.
Lockheed Martin has offices in both Colorado Springs and Denver.
If your looking for a job in the high-tech corridor, Colorado Springs probably would be your best choice right now. Denver is great and has more, but the high-tech corridor is lagging currently while the high-tech corridor in Colorado Springs has caught up a bit better, although still not too great. The economy in Colorado is very soft now, because the high-tech corridor was hit the most (particularly software).
If you want to live in a more pleasant atmosphere near beautiful scenery, then Colorado Springs is definately where you should move. If you want cleaner air and staying away from the hecticness of big cities such as where you are currently, then Colorado Springs is definately the place for you.
Denver currently has the 7th worst traffic congestion in the nation, although a major project to add additional lanes and light-rail in the southeastern part of Denver (where the traffic is the worst in the entire metro) is going on currently, however it won't be completed until 2008.
If you want to be in a more culturally diversed area, then Denver is where you should move. If you want to move to a place with a true city feel, has lots of entertainment, then Denver is where you want.
It really all depends on what you want.
Like Shawn mentioned, you could live outside of Denver or Colorado Springs such as in Castle Rock, Gleneagle, Boulder (well, that's not such a good idea
), Monument/Palmer Lake and commute to work daily.
However, if you live in Monument/Palmer Lake, then plan on working in Colorado Springs. The commute to the outskirts of Denver take 30-45 minutes depending on traffic and if your work is more inside Denver, plan on at least a 1 hour drive. With rush hour + road construction, your daily commute can take up to 2 hours.
Castle Rock is a good choice for you, although it is growing extremely rapidly. If you don't like growth, then you won't like Castle Rock much. There are condos, houses, department stores poping up like flowers. It's located in Douglas County which is currently the fastest growing county in the nation.
If you prefer to use public transportation (as you might be used to in Los Angeles possibly), well I hate to break it to ya, but there isn't much of it in Colorado. Colorado is a car loving state, although Denver does have a pretty good transit infrastructure with buses and a small light-rail system that is being expanded. Colorado Springs has a very poor and limited bus service which is a complete joke.
Wherever you choose to move to, I'm sure you'll enjoy. Both Colorado Springs and Denver have there pluses and minuses. It all depends on what your are looking for.
Hope this helps.
P.S. If you're concerned about smog in Denver, don't worry about it. That's a thing of the past. Denver had smog problems in the 80's and now has greatly improved it's skies. It's a heck of a lot better than Los Angeles, I can tell you that.
"Generosity is giving more than you can, and pride is taking less than you need." - Khalil Gibran