Yeah, I'm basically looking for this without 30 USD price tag.
I need software to record voice from mic, possibly in high quality, at a press of a hotkey - basically FRAPS for poor people. (I DO have FRAPS, it can't record voice only thou.) I don't really need all the fancy features like mp3 conversion.
Also, if someone was able to link me to a free video editing soft, basically to merge original's audio and a new track, I would be most grateful.
... Or I could find a better way to practice my english than making LP of System Shock, like talking to people. Nah, too normal. Besides, I have been battling against framerate issues (yes, in SS1 under DosBox while recording) and tried out too many audio recording software to give up now.

Hang on, do you want video or audio editing?
Audacity is a good bet for the latter, http://en.wikipedia.org/wiki/List_of_video_editing_software has a list of video editors, freeware included

Audacity really records everything: Including static and I couldn't find a way to filter it. As well as I couldn't find any off-focus hotkeys, so I can't really use that. Oh, yeah... I need video editing, I basically need to add external audiotrack to the video created by dosbox

With the main question I can't help ya, but for pasting audio on top of your video, simply use Windows Movie Maker, it's really easy to use and it's free. Furthermore, the Vista/Seven version of WMM shows great improvement over the XP version, in case you didn't know.
A lot of people recommend Virtual Dub as THE free video/audio mixer, but I'm too stupid to figure it out. One thing I can tell it should do better than WMM though is a better output, with less loss (still not lossless). Check outr virtualdub.org.
That static is probably because you're using a shitty mic, non?

Well yeah, but I won't be buying an expensive hardware just for some experiments, also it's not all that bad when using one of the seemingly-free-actually-trial recording thingies, nor is it bad under FRAPS. Maybe it's just bad settings in audacity, but... Well, that's it: I really didn't want something complicated. Hmm, I guess I'll have to toy around with it for a bit. Still, it doesn't have the off-focus hotkeys, which makes whole thing pretty much useless to me right now - or I just didn't find that between all the settings
Oh also, thanks for the recommendation, I'll try out the Microsoft ... thingie.

One of the problems is that all PC mics are shitty. It's something to do with the basic level of the mic signal on PCs having to be higher because PC soundcards don't have proper amps (I am speaking from memory here, someone explained this to me a long time ago). That, and the fact that they have to be so small add up to crappy mics.
If you buy a real microphone and plug it into your sound card, you'll find that the signal is so weak that it's useless. It needs to go through a pre-amp first in order to be useable.

If the sound looks better on other programs, it's probably some settings on Audacity. Once I had a similar problem, I solved it turning off all sound input and output other than the one I was recording, and it worked (it wasn't Audacity but was a similar problem).
About the off-focus hotkeys, I know this might not be practical (not sure what you're trying to do), but if you lack other options and you absolutely have to be skipping Audacity's window on and off, you can always cut the irrelevant parts of the audio on WMM later.
Aliasalpha just gave you another great idea, recoding it with a cellphone might just do the trick!

First I'll try the first, 'cause I'm lazy. But why didn't I think of using my netbook darn it? Well I can just do that, yeah :D Thanks for the idea, I'll wait if someone posts something to actually fit my laziness and give you the rep if no one does :D
My cellphone would disagree :D

Sony has a reasonably priced package ($100) in the Vegas Movie Studio 9 Platinum Pro Pack that works for video and sound. It's not free but you get a lot for your money . . . =)
Edit: I should mention the learning curve is fairly steep. Not as bad as Vegas Pro or Sound Forge but still . . . it will take some effort. However, your results will be great.

You're a bit thick?
The biggest advantage of a second computer is that it takes the processing overhead off the one you're gaming on. If you're capturing video on it as well as gaming then its already doing a good chunk of work

You have answered everything, and so you win!

Mwhaha more rep for me! Shame its as useless to me as bioware bazaar tokens...

I see what you did thar