1) Welcome to the Party!
2) As you are obviously new here, I have some suggestions to help us all help you:
When you post, please post your entire configuration including (but not limited to) your installation method (7.X.X?) and vicidial version with build (VERSION: 2.X-XXXx ... BUILD: #####-####).
This IS a requirement for posting along with reading the stickies (at the top of each forum) and the manager's manual (available on EFLO.net, both free and paid versions)
You should also post: Asterisk version, telephony hardware (model number is helpful here), cluster information if you have one, and whether any other software is installed in the box. If your installation method is "manual/from scratch" you must post your operating system with version (and the .iso version from which you installed your original operating system) plus a link to the installation instructions you used. If your installation is "Hosted" list the site name of the host.
If this is a "Cloud" or "Virtual" server, please note the technology involved along with the version of that techology (ie: VMware Server Version 2.0.2). If it is not, merely stating the Motherboard model # and CPU would be helpful.
Similar to This:
Vicibox X.X from .iso | Vicidial X.X.X-XXX Build XXXXXX-XXXX | Asterisk X.X.X | Single Server | No Digium/Sangoma Hardware | No Extra Software After Installation | Intel DG35EC | Core2Quad Q6600
3) There is an old vTiger/Vicidial integration which still has code in Vicidial. However, that code is for a very old version of vTiger and has not been updated for quite a while. You have the option of updating the old code or building a completely separate CRM integration method.
4) Note that in most cases, you will find that there is no actual need for vTiger unless you have multiple sales to individual clients.
5) Also have a look at SugarCRM before you settle on vTiger if you have not already considered the options. Each has advantages (sugar's code is cleaner and their interface is superior ... but vTiger has more features). Both kinda suck at email and have their own bugs (or "features" they like to call bugs, such as disabling POP3 in certain versions or a simple typographical error "private private" that breaks email functionality altogether, LOL).