Hi I hope someone can help me please...

I have a Hauppauge TV GO (PCI) card that works fine on my 700mhz Windows XP machine to capture AVI files at a resolution of 325x288.

The question i have is regarding codecs and how i can tweak them on my PC to make a smaller file size.

The Hauppauge WinTV2000 software with my card allows me to specify codecs in two different areas - which is confusing me!
Under the menu 'AVI Recording' and submenu 'Set video format' it asks for me to specify the 'Colour space/compression' (of which in my list i have RGB24, RGB32, YUY2, YVU9, UYVY, YV12, I420 and RGB555 (16 bit)). My setting is currently at YUY2.

But also on the system under menus AVI Recording' and 'Set Capture File' and 'Video Compression' i can alos set different compression types (and audio compressions). The options in my video codec list are No Compression, Cinepack, various Indeo codecs, various intel codecs and various microsoft codecs. My current setting is no compression!

Question 1 - can anyone please explain why there are two different areas to set the codecs? and why I have different lists? (and what the 4 digit codes are)

Question 2 - Using my current settings in these areas i can record about 1 hour 30 on my free 30Gb of hard disc before i run out of space. Can anyone suggest alternate settings that could get me longer? (I currently get no dropped frames with these settins and dont want to compromise quality too much). I have tried to change these settings to others in the lists but dont really know what i am doing and often get a warning that the changes i have made are not compatible and it changes them back!

I have been on the hauppauge website and seen their chart of different codecs, the dropped frames and resulting file size - but this doesnt make sence to my situation as I dont have the 15-bit RGB or BTYUV codecs in my list which they always quote!

Any help would be greatly appreciated. Thanks