It would be of no use if the operating system was a good one but didn't have the necessary applications to perform your day-to-day activities, like sending an email to your friend or listening to songs on your computer. I have provided a list of common tasks and Linux applications for them along with their Windows counterparts.
Accessing the Internet is as almost as simple as Windows. Both KDE and Gnome provide integrated dial-up managers similar to Windows. However, make sure that your modem is supported before trying to access the net through Linux.
Browser - Internet Explorer (IE)
In Windows, Internet Explorer is usually pre-packed with Windows. In Linux, you have many choices. You can use Konqueror, Mozilla, Netscape, Opera or Galeon. Mozilla is the better alternative to Netscape, and is bundled with almost all the distributions. Mozilla has made significant improvements in stability and to the user interface.
E-Mail Client - Outlook Express, Eudora
For those familiar with Outlook and Outlook Express, an email client that has a very similar interface and a good set of features called Evolution http://www.ximian.com/products/ximian_evolution is available for free. Linux also supports many traditional UNIX email clients like pine, mutt and elm. In addition there are a number of email clients designed for the graphical environments (KDE and Gnome). KDE has an integrated email client called Kmail. Gnome users can be comfortable with Balsa.
Instant Messengers-AOL, Yahoo! and MSN
Yahoo! and America Online (AOL) provide Linux and Windows versions of their instant messenger clients. I would very much recommend a multi-instant messenger client called Gaim that has an AOL interface and support for MSN as well as Yahoo! users. I have been using the Yahoo! messenger in college for about a year and I found the chat room feature and some other gimmicks to be missing, but overall it seems to be good enough for a development release (version 0.99).
Download Manager - GetRight
Mget, which is a non graphical utility, can automatically resume downloads when they are interrupted. Caitoo is a download manager similar to GetRight. A better alternative would be Prozilla http://www.prozilla.genesys.so, as it significantly improves the transfer speed by downloading the same file in four parts. It does not integrate with the browser but it is very much functional. If you are using a modern browser like Konqueror it takes care of resuming downloads by itself
Firewall - ZoneAlarm
Linux has long since come with built-in firewalls such as iptables and ipchains. The RedHat distributions usually have options for configuring the firewall even during the setup. If you need more software like this you can freely download them from the Internet.
FTP Clients and Telnet - Cuteftp, WsFTP
Linux supports FTP as well as Telnet from the command-line. A better option would be the Midnight Commander (mc) which is similar to the Norton editor. These are more intelligent than the versions supplied with Windows NT and 2000. Gftp, with a graphical interface is also available.
IRC Client - mIRC
IRC is a form of chatting that is popular with the geeks more than other instant messaging clients. Graphical front-ends are available in large numbers. These may be complicated to use at first but are very much capable of doing all that you want.
Newsgroup Reader - Outlook Express
I don't know how many people use these under Windows. Linux development and usage is very much dependent on the coordination of users over the Internet. Newsgroups form the basis for some of important tasks. There are many such newsgroup readers for Linux. Pan is a classical utility, very popular among UNIX and Linux users. A more modern alternative would be Mozilla Mail or Ximian Evolution.
Multimedia is a specialised segment where users are mostly Apple Macintosh fans, especially so with the release of OS X. Beos tried to position itself as a multimedia operating system based on the Intel platform, but has been acquired by Palm.
Music Player - Winamp
XMMS is a Winamp clone for Linux that has the same the look and feel as well as the functionality. It even supports the Winamp plugins. Both KDE and Gnome have a lot of other players available but I have being only using XMMS. There are no shortage of command line players either.
Movie Player - Windows Media Player
Gnome has a built-in player called GTV, and several others are available depending on the particular format of the movie that you want to play. Mplayer is used for viewing the Microsoft formats. With the release of crossover office from http://www.codeweavers.com. Even support for the QuickTime movie format has been added.
CD Ripper and CD Burner - Nero
Cdparanoia is a good CD ripper for Linux. It seems to be in the development stage yet though many people are using it on production systems. It is known be to stable and robust. Cdrecord provides command-line CD burning software for Linux. Problems with CD burning such as buffer under runs have been dealt with and it's now a fast and effective task.
Image Browser- Acdsee32
Gqview is an excellent image browser for Linux, built for the Gnome desktop, but nevertheless usable under KDE. There are other image viewers also, namely KView, Electric Eyes, etc.
Image Editor - Adobe Photoshop
Gimp is a powerful image-editing software, which comes for free, along with the source. It is considered as a professional tool but lacks CYMK capability, which is used by the publishing media.
Games
Quake 3,Unreal Tournament and Doom are some of the popular 3D shooter games available for Linux. The number of games available for Linux is usually way behind Windows. Several commercial solutions are available from vendors such as Transgaming's WineX http://www.transgaming.com which is capable of running Windows-based games on Linux.
If you like board games and puzzles better, you will definitely not be disappointed. On average, over 50 such games are bundled with Linux. I like Tuxracer, a simple 2D race game and Sokoban, a simple yet appealing strategical game, to make the time pass.
Office Suites - Microsoft Office
StarOffice from Sun is the popular alternative. It has an integrated interface that can act as a virtual desktop and includes a word-processor, spreadsheet, presentation software, browser, as well as a e-mail client, rolled into a single application. One of the common complaints is that it is slow to load. This office suite has become a paid version starting from Staroffice 6.0. Sun now provides a open source (free) alternative called Openoffice (http://www.openoffice.org). If you just require a word processor for typing out letters and stuff you can try using Abiword (http://www.abiword.com).
Antivirus - Norton and Mcafee
Viruses are a much lesser threat to Linux. They are very few in number and they cannot affect the system files unless in a well configured system where you are not a root user (administrator). Linux is not immune to viruses but you shouldn't be worried about them as they don't possess a significant threat. I've never required an antivirus program, and it will probably remain that way for some time.
Maintenance Utility - Norton Utilities
Administrative things such as setting up user accounts and stuff is the only kind of maintenance required by Linux. Since Linux is designed to run in a server-unattended mode for several weeks it does not demand day-to-day attention like Windows. I am not aware of anything similar to Norton Utilities for the simple reason that it is not at all needed.
RPM Find provides a large variety of Linux software in RPM format at http://www.rpmfind.net
Sourceforge provides source code for upgrades and new Linux software projects at http://www.sourceforge.net