Well, if it isn't a financial hardship, then perhaps a memory upgrade would help. Win7 64bit should run comfortably on 2GB, you have 3GB, but 6GB would probably speed you up somewhat. You might increase the size of your page file as a HDD is the bottle neck in today's computers.
Other then that, perhaps running
RevoUninstaller Free and doing an advanced uninstall on seldom used software would help. Then another 'Chkdsk' followed by a 'Defrag' might help after that's been done.
I don't have a Win7 machine available to test this on but perhaps this:
Win7 SDK might work. You'd want to use the Performance Toolkit portion. I believe it's a Win7 equivalent to
Bootvis, which is a great little program from MS that helps speed up boot times in WinXP.