'invalid command line argument' - Most probably the SAPinst is not able to find the right path for the DB2 UDB DVD or the the argument is too long to interpret which is a very common problem during installations.
Check the path for db2 DVD, and keep it shorter - that means you have to reduce the number of folders where the DVD resides. Copy the DVD in a short path let's say C:\DB2\dvdname and re-try installation by giving the new path of dvd in SAPinst.
Thank you.
