Mirabella and Camden are two decent apartment complexes near Pop Century (intersection of Osceola and South International) if you want to live REALLY close and still be in safe, out-of-the-way neighborhoods. Though they are a tad pricey (800 for a 1 bed, 1100 for a basic 2 bed, ect). There are some apartments at the intersection of 192 and 27 (Cagan's Crossings) that are ok. Price is MUCH lower than the above mentioned, but it's further from The World and 27 is usually a mess of construction. There are some decent areas in south Kissimmee (The oaks, but that's a home community, not apartment, but lots of homes for rent). Poinciana is very inexpensive but it's also a 40 minute drive. Windermere is not bad at all, but price wise you're looking just a little less than celebration. In general, the further away from The World you get, the cheaper it gets.
As far as metro west, avoid!!! 8 Murders this year so far, and add that with 3 confirmed rapes, not very good statistics. They look nice, but they're next to Tangelo Park and some other not-so-nice areas.