Chances are the transaction is rolling back. You'll just have to wait for it. 90 GB is a fair bit of data. Sometimes it can take significantly longer to roll back a transaction than the time it took to get it into that state. Is this happening in a test environment? If so and you do not care about the database at all you can have the DBA forcefully remove the database from the instance and just start over to save a little time.

By the way, you posted in a SQL 2000 forum but said you are on SQL 2008 R2. Click the Forums link in the left nav to see the list of forums on this site. There are several for SQL 2008 that are more suited for future questions relating to the system you're on.