MC 4 does not play p2 media smoothly.. help me please

Hi.. I am using Avid Media Composer 4.2

before some days am committed a HD project.
But after inserting the MXF file from p2 media(Camera : hvx301) , avid MC4 does not playing it smoothly.. both in full screen and also in sequence..

My Sys configuration is:

Processor :intel Core2 duo E4500 @ 2.2 ghz
motherboard : D945G
RAM : 2gb
Harddisk : 250 gb for boot and 1 tb (7200)for data
Graphic card : Nvidia Getforce 7100 GS (512 MB)

Avid problem when playing video on composer/timeline.

hi,Everybody
I have having problem on avid express pro 5.7.2.
when i import the video and drag to timeline and i hit space bar and try to play manually, It doesn’t plays. on the same video when i scrub the timeline it plays like normally….like it plays on scrubbing the timeline. and second problem is my omfi media files are always made on last drive of the computer.

Friends i am using windows xp sp 3 built 2600 version 5.1, with 2GB DDR2 ram 2.8GHZ Pentium D computer with Nvidia 7300GT graphic card and Intel 965 motherboard.

Please suggest what i should do to solve the problem.
sorry for Bad English.
sawan

Avid to AFX

hi!
anyone knows the way to translate an Avid MC timeline to an After FX comp or Fusion? On automatic fashion, of course.

thanks a lot!