Softwares

I always hav and would continue to prefer Windows OS's over any others as they r easy to use :P, i use and found a bunch of such softwares:

Video Players:
After using VLC Player for a long time i was searching for a player which could even play RM Formats, found these players which does'nt even ask for manual installation of codecs and also sound quality it gives is amazing:

• GOM player:
  

GOM Player is a visually appealing video player with very interesting features and which, above all, solves any problem you may have with codecs.
Languages: English

• GOM Player supports the following formats:

  GOM, AVI, DivX, ASF, ASX, WM, WMX, WMP, WMV, WVX, MPEG, MPG, MPE, M1V, M2V, DAT, VOB, MP4, 3GP, K3G, LMP4, SKM, DMSKM, RMVB, RM, OGM, MKV, IFO, DMB, OGG, AC3, XviD, H.263

  OS requirements for GOM Player: Windows XP,Vista

You can download this player at http://gom-player.en.softonic.com/download.

• KM Player:

Another player which i found amazing was KM player, this also plays all the above formats and works fine with XP and vista.
Download link for this player is http://kmplayer.en.softonic.com/download.

Both these are freeware :) and also these have features like if u have som movie files under the same folder and play one of them, these players pick up the others automatically and plays them for u which i think cool :).

There are also other players like Real Alternative, Total Video player and BS Player which i dint like as much as these players.

File Encoders(Converters):
I was lookin for a file converter which could encode most of the file formats. Found this Universal encoder called SUPER.
This tool is pretty fast and also can encode full length movies. Has almost all the neccessary codecs builtin.
Supported input source file formats are:-

Image Sequence: jpg, pgm, png, ppm (with sequentially numbered-ONLY filenames) having the same filename numbered-ONLY format.

Video format: 3gp/3g2(Nokia,Siemens,Sony,Ericsson), amv, asf, avi(DivX,H263,H263+,H264,XviD,MPEG4,MSmpeg4...), dat, drv-msfli, flc, flv, m2ts, mkv, mpg(MPEG-I,MPEG-II,VCD,SVCD), mov(H263,H264,MPEG4,SVQ..), mp4(H263,H264,MPEG4..), nsv, ogg, qt, rm, ram, rmvb, str(Old Play Station), swf(Flash), ts(HDTV), tmf, ty+, viv, vob, wmv.

Audio format: aac, ac3, amr, mmf, mp2, mp3, mp4, mpc, ogg, ra, wav, wma
Download link for this software and all the details can be found at this website: http://www.erightsoft.com/Superdc.html This is also a freeware :)