>>>Hi,
>>>
>>>I came to the screen where I can download SSMS Express 2008 R2. The choices are 32-bit and 64-bit (I can guess by the names of files). My computer is Windows 7 64-bit. So naturally I should be downloading the 64-bit version. But - here comes the newbie question - is there such a thing as 32-bit SQL Server? That is, if my copy (or customer copy) of the SQL Server is 32-bit (and how can I find out?) will the 64-bit SSMS work? TIA.
>>
>>Yes - the 64 bit SSMS will work with any SQL server version.
>
>BTW, I already have a SSMS 2005 installed on this computer. Should I uninstall it before installing the SSMS Express 2008? Or the two can coexist?

They can coexist, but I'd uninstall 2005 because 2008 will do everything 2005 did (and more).