ORM
ORM allows you to map your database entites with dataaccess layer entities.
NHibernate is proven ORM data access layer. it is also a supports variety of datasource.
while LINQ is newly growing Microsoft Technology and its preliminary version that is Linq to sql is stick to SQL server.However it is also possible to create your own provider for other datasources.
Now They have released Entity Framework that is more generic in nature.
So,Microsoft is also providing extensiblity to any of their framework.
As per me it is better to go with Microsoft products so that any changes or newer functionality releases you can adopt it very faster and that fuctionality always supports backward compatibilty.
CRM
This CRM is an Enterprise-Class Customer Relationship Management server written in C# for the .NET platform with many advanced features like Companies/Leads/Contacts Manager, Calendaring, Groupware, Email Marketing, Reporting, Orders, Catalogs, etc.
Asp.Net CRM is a free, web-based Enterprise-Class Customer Relationship Management server written in C# for the .NET platform.
With many advanced features like:
* Company and Contact Management
* Lead Management
* Calendaring
* Tasks
* Notes
* Messages
* Opportunity Management
* Activity Management
* Advanced Search
* Charting
* Case / Solution Management
* Reporting
* Internationalization
* Companies, Contacts, leads and activity Import
* Advanced Reporting
* Product Catalog
* Email Marketing and Mailing Lists
* Mobile/WAP Access
* .Net WebServices
* Forecasting
* POP3 email manager via WebMail
* Voip Integration
* Microsoft Outlook Email Integration
* Desktop Alerter
* Quotes
* Knowledge Base
* Dynamic Databases
* Trouble Ticket Management
* Business Intelligence
