Open university - need some info please?

I'm 25 and work with adults with learning disabilitys for the government. I joined the job 7 years ago after studying an AVCE in Health and Social Care. I planned on going to Uni to study Social Work after a year or so of experiance in the job. It didn't turn out as planned and 7 years on i'm still in the job - it is a job I enjoy. I want to continue working there however I also want to study to eventually become a social worker, so I was thinking I could do an open university course for Social Work along side my job. I have only skimmed through some information on the net and will have a proper look. I was wondering if anyone else has been in the same situation and if it is feasible - how much money am I looking at spending to complete the open uni course, can I get grants? Will my job (currently with my local borough) help me out? I'm due for an appraisel at work soon so want to ask them about it but want a bit of knowledge about it before hand so I know what i'm saying. I work 37 hours a week. Any info would be very much welcomed, thank you.