So here we go!!!!

First of all thanks to these bloggers:
http://boston-mania.blogspot.com
http://albert-david.blogspot.com/2010/10/rooting-spice-mi-300.html
Most important thing to remember :
As I have already pointed out that Videocon Zeus V7500 is clone of Commtiva Z51 and it lacks trackball.All ROM's you may find on net are developed for Z71. As result most default recoveries are unusable with V7500 because most of them require selection of item by pressing trackball. So we may use clockworkmod z71 recovery (for boston, z71 and clones),which is the only one other than stock recovery which I found to work with V7500. Also it is important to keep in mind that at any given point either the recovery or the rom(android os)should be in working condition to avoid possible brick.If both work then its better.
I'm using 64 bit Windows 7.Also enable USB debugging on your device from"settings->applications->development"
I assume that we have official 2.1 ROM installed. First we need to root the device. z4root1.3(get it from 4shared.com) will do the job. First we will backup the official recovery.

When you connect you phone to PC you will see some thing like this.Also click OK if it promts to run setup.exe.   Open and copy the contents of this drive  to some folder, for example folder named "driver" in our case. So if you put the folder named "driver" in your D drive; you will do cd d:\driver in command window(run cmd on windows).
This is just to give an idea. it is running on 2.2.1

 To run the adb  run command:
adb shell
you will see message that some is service is starting.
now use su to get superuser access. You will need to provide access on your phone, so keep an eye on your device as you enter su command.
Also disable USB storage. You should not be able to see your sdcard.
Do:
cat /proc/mtd
to see partitions on your phones
cat /dev/mtd/mtd3 > /sdcard/recovery.img
to backup recovery partition on sdcard.You will have recovery.img file in root of your sdcard, backup the file in some safe place.
Now download rom manager from market and install clokworkmod recovery for Boston,Commtiva z71 clones. Power off the phone and restart by pressing camera+vol.up+power to get in recovery mode, press camera button forcefully or you will have normal boot. Once in recovery mode we will backup our stock ROM. Clokworkmod is designed for z71 i.e trackball so when we use any key it behaves bit oddly in Videocon Zeus. One key press is registered twice. So if we are on menu item no.1 and want to go on menu item no.2 by pressing vol.key only once, we will actually go to menu item no.3 in clockworkmod recovery. Work around this is to simultaneously press both vol up+vol.down keys. Just try few times you will get to know how it works. We press green button(call receive)button to select menu item. Now it is also registered twice. So when u press green button you automatically end up running first item on the sub-menu. Workaround it is to keep holding atleast one key till you have reached desired menu item. So to select  second item on submenu you will browse to desired item on the main menu using vol. keys. keep holding volume key and press green key. As soon as you press green key you keep holding it and leave the vol.keys. Now browse submenu using vol.keys. Try it you'll understand what i'm trying to explain.
Now backup your stock ROM using appropriate selection in clockwormod recovery. Copy this recovery files from sdcard and keep it in some safe place on your hard drive or burn to cd.

Videocon Zeus running Clockworkmod recovery and froyo.

Cyanogenmod 6.1 on Videocon V7500 zeus

Rooting and Updating / Upgrading Videocon Zeus V7500

Videocon Zeus V7500 Evolve is re branded Commtiva Z51  being sold in India by Videocon . In India there is also other Commtiva re branded Android phone from Spice, known as MI-300. It is clone of Commtiva Z71 though. Only difference between Z51 and Z71 is that Z71 has a trackball whereas there is none on Z51.

Now bad part for Zeus users is that Z51 is virtually unknown phone globally, but the good part is Z71 is pretty well known and has many clones across the world and all its roms are easily applied to z51.
Since the underlying electronics has been manufactured by Foxconn it seems as if in Z51 they simply did not provide the trackball rest of the thing being same.

Now about rooting the phone.

The phone comes with android 1.6 (from late November it will come with android 2.1). The 1.6 version is easily rooted by downloading and installing Universal Androot application.
Since last week of November official 2.1 update is available from Authorised Service Centre (ASC). This version is easily rooted by downloading and installing z4root application.
Also you will need to install this version if you want to upgrade your phone with the method mentioned here.

Why upgrade ?
 Firstly 1.6 is downright lousy if you want to surf the web.
The official 2.1 update limits the processor speed to 480 Mhz to save the battery.

What happens when I upgrade?
You will have Froyo 2.2.1, browser in this version is really fast. You will be able to run your processor at its stipulated speed of 600Mhz. Also you can move/install the programs on sdcard.
You wont be able to run Adobe Flash though. Flash requires ARM7 processor whereas all models mentioned here have ARM6 processors.