How do yo keep your computer running at it best?

What kind of free programs are out there to help keep your computer running at it best?   What do you recommend?

Well, smart browsing and usage will always trump even the mightiest of cleaning/defense programs. But, even the best of us get loaded down with stuff over time. I personally have had very good results with CCleaner (or Bleachbit for Linux). I haven't used a paid antivirus in over 13 years and haven't had a virus in the same period. If you have an HDD (NOT an SSD), Defraggler is a good way of keeping it cruising along. [I personally experience better results with it than the built-in Defragmenting Service of Windows]. Programs like Revo Uninstaller are also good to make sure you get every last little bit of a program gone when you are done with it.

Each person tends to develop their own series of programs and routines, mine is fairly minimal, entirely cost free, and works for me. I'd go with whatever gives you the best piece of mind based on a patchwork of programs

No problem! 

Your first and most important line of security is your commonsense.

if you are savy about the net then you can get away with a good free av, but most are not for those people I recommend ESET Smart Security and Malwarebytes, for AV/Firewall/Anti Spyware.

the thing with paid AV apps is that they automatically update and an AV is only as good as its update.

thats for security for up keep as Tidgxor pointed out CCleaner, this app is really an all in one app:

1. it cleans temps files in one click, you can set what app to clean or not.

2. its an uninstaller, so instead of add/remove programs, you can use ccleaner, its loads much faster then the default windows add/remove app.

3. you can easily edit your startup programs, you can disable, delete or re-enable, much eaiser and better and infact recommended way of editing your startup apps instead of using msconfig.

4. registry cleaner, tho we don't recommend messing with your registry unless you have issues.

5. duplicate file finder

6. drive cleaner

7. system restore management

8. you can add custom files/folders to be cleaned/emptied.

so as you see CCleaner is a great tool to have.

another important app would be Acronis true image, but IMHO only the clone part of this app is great as images can get corrupt or fail, you should clone your drive once a week that way anything goes wrong worst case scenario you only lose one week data, of course if you clone more then one once a week you lose even less data.

Cloning is great because its basically a duplicate of the whole drive, if the original drive goes bad then all you have to do is replace clone with original and boot back to windows as you normally would and go about your business.

personally I never reinstall my OS, my win7 is now about 3 or 4 years old and I put it up against a new install anyday, not that any human could tell the difference between the two on a ssd to begin with.

so thats my 2 cents, everybody is different to each his own