Noise Artifacts & Grainy Picture

Hi, i wish to send this message as regards trying to obtain a sharp, smooth, clear image & quality picture when capturing audio visual material from DVD Regions 1 & 2 (PAL & NTSC), so far i have been using the Blackmagic Ultrastudio 3D Video Capture Device to capture audio visual material from a Sony DVP-NS76H Multi-Region DVD player via the Thunderbolt connection onto a 27 inch iMac with the following specs:- 3.4Ghz Quad-Core Intel Core i7 16GB 1333 Mhz SDRAM – 4x4GB 2TB Serial ATA Drive + 256 Solid State Drive AMD Radeon HD 6970 2GB GDDR5; Two Thunderbolt ports Mini Display Port with support for DVI, VGA, and dual-link DVI One Firewire 800 port Four USB 2.0 ports SDXC card slot Slot-loading 8x Super Drive with 4x double-layer burning Audio in/out; and i have been using Final Studio 3 software on the captured footage, i used the 2TB drive to store my projects & Captures & renders etc.

But i have been disappointed with the quality of the picture which is grainy has noise artifacts as though there are invisible microbes crawling all over it. Can you tell me what can be done to eradicate this as the quality of the original source DVD footage is not in question, (i have considered using the G-Tech RAID 6 TB 7200 RPM Drive as a capture scratch disk and to store renders etc, would that help me capture audio & visual footage at the optimum quality it can be) Can you give me any advice & tips as far as choosing & selecting from the Final Cut Pro 6/7 Menu -

User Preferences: General, Editing, Labels, Timeline Options, Render Control, Audio Outputs;

System Settings:Scratch Disks, Search Folders, Memory & Cache, Playback Control, External Editors, Effect Handling;

Audio/Video Settings (Easy Setup…):Summary, Sequence Presets, Capture Presets, Device Control Presets, A/V Devices;

Would that be the key to resolving this issue?