I just went through this with my baby sister. I wanted something that was safe, reliable and awd. She wanted good gas mileage and cheap (preferably under 25K). Our short list for new cars was suburu (several models), cr-v/rav4. I'd look at suburu first, especially if you're thinking new.
Used opens up a lot more options --- for a while she was driving my 05 G35x. safe, reliable, awd, but averages 20 mpg. I think used 05-06 are around $15-17K. For low 20s you can get into 07+ (newer body style).
After debating safety vs size vs cost vs keep for long term or not? vs lease vs used vs . . . . we finally decided and picked up a 09 CPO 535xi sedan. Yeah, not exactly $25K but not that much more, and has everything (safety, size, gas mileage, etc) that we want.
09 335 vert - ED Feb 09
06 325 vert - gone
05 G35x - winter