Bad looking résumé help!

Hi,I graduate in May 2013-adult gero program. I have been a RN since 1991. During that time I've had many fully time jobs and also worked at agencies, or two facilities at the same time being either part time or full time at one, then prn at the other place.Well I sent my résumé this past week for a geriatric position at the health network I am already at and she mainly asked me (recruiter, not manger) about when I have been part-time, full time and started with my first job as a GN in 1991!Anyway, I talked to my preceptors and they suggested I take off my prn/agency jobs and just list relative experiences. My résumé is functional informat at this time to summarize everything, then just list employers on one page. Right now that takes up most of page, if I take out prn/short term jobs it shortened it about 1/2.Any input is appreciated. I am sure I am not the only one who has had this problem.Thanks!