DB2 shouldn't have issues at all with storage of large files. Some of how you store them will depend on what exactly you are storing. Are you storing XML files? Large text files? Word documents or PDFs? Video? Audio?
You have several options available to you. Graphic strings, binary strings, your large objects (CLOB, BLOB, and DBCLOB), and just plain XML.
If you are using just character data I would side with a
CLOB. But check your sizes, if you are consistently lower than 32K it might just be better to use a
VARCHAR. (Reason being is that large objects in DB2 are stored outside the table by default (unless you use the
INLINE option, but even then it only works to certain sizes of LOBs), and they are also not cached in bufferpools. DB2 always retreives LOB's straight from disk (unless they are
INLINE'd as mentioned above). If you are storing XML documents, you might want to look into the
XML type as DB2 has a more optimal way to store and retrieve XML. You can set up special XML indexes on XML types too. And you can query the XML using SQL/XML or XQuery using XPath.
If you are storing binary objects, then I'd go with
I think you may be right about the compression piece. (Although it wouldn't hurt to test it. There are about four or five different compression levels in DB2 and I know I can do at least backup compression with 9.7 Express-C).
Here is a 10.1 Edition comparison chart. And here is a article on the different editions and what they all offer.
Also take a look at space requirements for tables to help you better pick what you need.