Quashing

Hello,
1) The High Court can decide only the case that is before it and not the cases files in other courts.The case before the family court will have to be decided by the same court.Upon passing a verdict on the writ before it the HC can direct the parties to go back to the concerned Family Court to settle their case there.

2) If you wife is agreeable for divorce now without contesting, you have the option to convert the petition to a divorce by mutual consent or  your wife has to withdraw the petition before the family court and you have to jointly file a petition for Divorce by mutual consent.

3) As regards the Dv case it must be before the  court of a Magistrate. Your wife has to move a petition to withdraw the petition if your disputes have been settled.

4) High Court does not act as one stop solution and will not interfere unnecessarily in the working of the lower courts or in the matter pending before them.

1. Against whom you have filed the W.P. and what is the prayer in the petition? You can not file W.P. against a private indivual,

2. 498A can not be withdrawn by the complainant since it is not compoundable. she has to give such statement in the High Court, at the time of hearing the Quash petition filed by you (not W.P.), that the High Court quashes the FIR,

3. Divorce petition shall heve to be filed before the lower Court and not at high Court,

4. Ask your wife to sign a mutual consent divorce petition which will be decided within 6 & 1/2 months.

If the divorce case is pending before family court, it will be disposed n the family court only and not by high court. 
The 498a case is not compoundable hence a quash petition under section 482 cr.p.c. shall be option to get the same disposed if she cooperates for the petition filed by you on this.
She can withdraw the domestic violence in the trial court itself.

It is your own statement that your divorce case is pending in the High Court. So if a compromise is arrived at then the HC can dissolve the marriage in tune with the terms of compromise.

when parties to the proceeding appear before the court and submit their compromise letter then High court passes a direction and order and remand the case to the lower court to pass decree on mutual consent of the parties. High court does not  pass decree of mutual divorce.

On the basis of the statement of your wife the HC can allow the withdrawal of the case by her if she seeks court's permission to do this.

Now i want to ask 498a case once filed, how it can be withdrawn or there is any power with high court to dismiss 498a.
You can apply for quash of charge sheet under section 482 of cr.p.c. in which your wife as a respondent can file an affidavit stating that you both have compromised and made an out of court settlement hence she has no objection, as a defacto complainant, to the court considering quash petition filed by the petitioner. The high court, based on the affidavit of the respondent/wife, shall quash the case under 498a and you can be discharged from the case. 

1. Section 498A of IPC is non compoundable which means that it can not be withdrawn,

2. In this regard only option before you is to get the said FIR Quashed by the High Court,

3. Get an affidavit executed and notarised by her affirming that she has amicably settled te dispute with you and that she has over acted due to uncontrollable rage and also that you act due to call for any police complaint u/s498A of IPC,

4. With copy of the said Affidavit affirmed by her and also to be deposed by her, if the Judge asks her questions, you should be able to get the said FIR quashed.