Since you're using MSSQL, if you're able to deploy a website then put together a little site that queries the system catalogs for the information you want to document. Connect to your database and go to Views -> System Views to see them.
I'd ignore the views in INFORMATION_SCHEMA because while they provide a more user-friendly format if you just want to look at them directly, they're lacking some useful information. The views in the "sys" schema contain everything.
The ones you'll most likely want to start looking at are:
If you have any problems figuring out the meanings of columns in those views, they're all documented in Books Online / MSDN. Most of those should be self explanatory, except maybe sys.extended_properties. That's where Management Studio saves descriptions. If you add a description to a table and save it, then right-click the table in Object Explorer, and select Properties then Extended Properties you'll see the description. You can add an arbitrary amount of extended properties to things, and this can come in real handy for documentation depending on what you want to document and how detailed you want to get.
If you want to allow descriptions to be edited in the site itself, you can use the sys.sp_addextendedproperty, sys.sp_updateextendedproperty, and sys.sp_dropextendedproperty stored procedures.
Finally, if you want to document where a table / view / etc. is referenced throughout the database, you can use the sys.sp_depends stored procedure to get that information.
The nice thing about this approach is that your documentation will be exactly as up to date as the database itself. Looking at a table definition and add a new column to the table? Refresh the page and it's there. Although, if you want to have documentation that's just a snapshot, you can do that too. And you get something you can navigate through and in a format that avoids the clunkiness of trying to read description fields in SSMS.