1. I installed K-Lite Codec Pack Could it interfere with my system?
2. Is there a recommended version of QuickTime for win7 64bit? (I installed the standard version on apple site and since the screen flickers for a second when i open premiere, Is this normal?)
3 . Is there any special setting for optimizing performance of my quadro 4000 video card?
I installed K-Lite Codec Pack Could it interfere with my system? [Block Quotes do not seem to be working today.]
Yes, it certainly can.
I recommend against installing aiy CODEC pack. One of the modules installed by K-Lite is FFDShow, and it has caused all sorts of problems with Premiere.
Which CODEC(s) do you need specifically?
I would get those, and install ONLY those. I also recommend going to the source, where possible, rather than a "free" version of the same CODEC. Now, there ARE some great CODEC's, that are free, like Lagarith Lossless and UT, but for a lot of the CODEC's, the commercial versions will be a better choice.
Never install a codec pack. Premiere has everything you need unless you need a particular codec which you can install seperately.
Codec packs can mess up your system, the only way to get rid of them is a clean install of Windows.
If you think QT causes the problems roll back one version. (Not only install QT but save also a copy to the harddrive.)
Make sure you have the latest driver installed for your graphicscard.