In general, I'd recommend starting with A+ and Network+ then moving into some vendor program -- be it Microsoft, Novell, Cisco or whatever (Linux/Unix, telephony, etc.) -- depending on what kinds of systems and platforms you'd like to manage in your next position. By the time you get the A+ and Network+, you may also have a better idea about what kind of platform choice you'd like to make for your next certification. If you're still uncertain at that point, write me again with more specifics, and I'll be happy to advise you further.
This was first published in November 2002