scan various pages into one document with HP psc 1215

I spent hours reading through all questions regarding HP psc 1215 printer. I would like to scan various pages into one document (and as pdf, not jepg). So I learnt from the previous users that I would need the HP solution center to do that. However, this solution center could not be installed completely and is therefore not to be used, at least this is the message I get. I deinstalled the HP solution center and now I am really clueless. Can you help please?

I am using Windows 7 64 bit

Thanks very very much.