Forseti is the best person to advise as far as getting the best footing to become a 50/50 shared residence parent, follow his advise to the letter!
If you are looking for suggestions as to possible asset split, you''d be best of copying your post with details above into a new thread, as some of the people best able to advise on that (little mr mike, dukey) tend to look out for financial related threads whereas this appears at first glance to be a child contact thread.
As for your specific questions in your op
do i need her agreement to file for the divorce ?
no, but if she is already getting angry at mention of divorce, it is probably best to go for two years with consent, you refer to separating amicably three months ago. I believe to show you are separated you need to show separate finances, and separate living arrangements in the house (eg, demonstrate that you have your own bedroom, or at very least a sofa bed in the lounge, cook your own food and do your own washing) but also bare in mine Forseti,s advise to demonstrate you have equal care of the children, so don''t fall into the trap of just doing your own washing, but factor in doing the kids, and cooking their dinner three or four nights a week etc. then hopefully, in two years time you would be able to get her consent for a divorce amicably.
can i stay put in my home for as long as i wish as i half own it ?
Yes. Forseti has already given you the best advise on this.
with the online packages here are the only really going to work if people are talking or in agreement ?
Yes, all fixed price quotes from solisitors assume that you are in agreement over the financial division of assets and living and contact arrangement for children, as the price covers writing this up legally and filing the appropriate documents for court. If there is any disagreement over either children on finances, it is impossible for the solisitor to predict what the costs would be (ie, whether a few letters would sort it or whether issues are going to go the full length in court with appeals on top) and therefore impossible to provide a fixed price.
Really, your best bet is to attend
mediation with the stbx to agree finance split and child care, and to try and get her over the anger stage, which hopefully is a passing phase as she comes to terms that her marriage is over, rather than setting the tone for things to come.