New here and need some lens advice...

I'm new to the forum here and somewhat new to "real" photography. To put things in perspective, most of my picture-taking has been with a Konica-Minolta Z5 (long zoom point & shoot), though I do have a "vintage" brown leather-clad ME SE that I inherited from a relative and used a bit. Tired of the Z5's inability to focus in poor lighting, I decided to get a DSLR. I ended up getting a K2000/K-m - the dual-lens kit - and am totally in love with it. However, the Z5 had a zoom range from 35-420mm, so I got very used to having that type of versatility. Consequently, I find myself swapping the 18-55 and 50-200 all the time, which I know is just inviting dust and damage into the camera.

So, I'm hoping that some of you who might have made a similar switch (from a long-zoom p & s to SLR or DSLR) could offer some advice. Should I just force myself to stick with one lens or the other? Should I go cold turkey, get a good 50 mm fixed lens and force myself to use that while I learn my way around the camera? Any guidance for a newbie would be appreciated.

-Chad