Re:Be realistic (Score 1)

This just isn't true anymore. OpenOffice.org is a perfectly capable office suite and recent compatability with Office has been pretty good in most cases. Performance has also improved, and will be perfectly acceptable on a relatively new computer.

Outside of Office software, Audacity is a great free audio editor

SciTE or the java-based Jedit are good text editors.

The GIMP is a good image editor, available here for Windows.

Mozilla or one of its components for mail/web browsing

For media playing you might want to try Zinf (formerly FreeAmp), Foobar2000 (nice light weight music player), WinAMP for Windows. MPlayer is a good video player for Linux (and Windows) and XMMS is a capable music player for Linux.

Celestia is a nice space exploration program.

Jabber is good for instant messaging or Trillian or GAIM if you need to chat on MSN, AIM, ICQ etc.

GNUCash is a capable accounting program.

Oh yeah, and for email, I suggest setting up an IMAP server on an old machine and using that to store your email. This can be quite difficult, though allows you to browse your email from Linux and Windows. Thunderbird is rock solid and good even though only in the early stages of development.