Windows 7: Semi-new to windows

I managed to find enough spare parts to put together a decent computer, and I decided to make it a Windows box. However I am normally a Linux or OS X user, with most of my Windows experience being years in the past mostly with XP.
Just wondering if there are any must have cool programs or tweaks that anyone can recomend?

If you are referring to Windows 7, there are none that reach the level of "must have" or even "almost a necessity".

Windows 7 works well in default configuration using only the built-in tools, assuming you keep it updated.

If you have specific performance issues, then start a thread about them.

If you reduce your requirement from "must have" to "recommended" or "pretty cool" or "what do you personally use", you will get hundreds of ideas, none of which are "must haves".

indeed what cool programs and customizations are there?

One man's cool is another mn's hot as they say. Surely it depends what you want the computer for. gaming, surfing or what?

I'm hard pressed to name any that relate to performance or stability beyond the obvious things like anti-virus, anti-malware, defrag, disk maintenance, etc.

The included Windows defrag and disc cleanup tools work well. As does the free Microsoft Security Essentials anti-virus. It's a download.

There's all sorts of eye candy ideas that are unnecessary and have nothing to do with performance or stability.

I have no idea what you might mean by "cool".

Things like 7-Zip and ImgBurn can be very useful to 'expand' on Windows 7's built-in features. I also find the FileHippo Update Checker to be very useful for non-Windows updates.

Coming from Linux, I think you'll like the changes in Windows since XP. The most-used would be the Start menu - if you find yourself browsing through All Programs searching for something, stop. Just press the Windows key on the keyboard, and start typing what you want - no more searching!

There're lots of little shortcuts/tricks that are handy, as well. Holding Ctrl+Shift when opening something (with double-click or Enter) will run it as Admin. Holding Shift when right-clickin on things in Explorer will give you extra options. Shift-click (or the middle mouse button) a pinned taskbar item to create a new instance; right-click for the Jump List (great feature). Etc...

Uh: I listen to and produce music; chat on IRC, aim, and Facebook; occasionally play a game and enjoy a well tuned system and good GUI. Just not sure where to begin on windows besides mIRC and I guess iTunes?

Are there any recommendations on drive encryption?

iTunes works, but it's huge and not needed for typical listening.

If you insist on iTunes, 10 year old versions work fine as a player, but I switched to Media Monkey.

I know nothing about IRC, AIM, Facebook, or gaming.

CCleaner is probably the single most recommended add-on app, but it's not a "must have". It's a disk cleaner and registry cleaner.

Most here would tell you to avoid registry cleaners of any type. Some say they trust CCleaner.

I would avoid software that claims it will "tune" anything.

Do ordinary disk cleanup, see that defrag is on a schedule, keep Windows up to date, use a good anti-virus and anti-malware app.

Take a look in Task Manager, Resource Monitor, and msconfig so you can get a rough idea of your memory usage, processes, and startup programs.

Familiarize yourself with Disk Management (built-in).

These questions are some of the most vague that are ever asked on here. We can't recommend software because only you know how or what you want your system to perform specific tasks and needs. Windows 7 runs efficiently out of the box and doesn't need tuning. Just update it and keep your drivers updated. IM programs died out years ago, but if you still need to chat with people clinging to the past, I guess the are a necessity. Just don't have them run at boot automatically. iTunes is some of the worst software ever written, so I wouldn't load it on a computer unless absolutely crucial. Music can be loaded and unloaded from iDevices with much better software, like MediaMonkey. Microsoft Security Essentials is free and does a good job of keeping the system clean. The rest is up to your needs.