I need to replace my existing standalone. I want to be able to edit a large number of home movie dvds (about 30 discs in tota

Solution
This'd suit your needs best:

PCPartPicker part list / Price breakdown by merchant

CPU: AMD FX-8320 3.5GHz 8-Core Processor (£97.99 @ Aria PC)
CPU Cooler: Cooler Master Hyper 212 EVO 82.9 CFM Sleeve Bearing CPU Cooler (£24.86 @ CCL Computers)
Motherboard: Asus M5A97 R2.0 ATX AM3+ Motherboard (£63.56 @ Scan.co.uk)
Memory: G.Skill Ripjaws X Series 8GB (2 x 4GB) DDR3-2133 Memory (£72.30 @ Amazon UK)
Storage: Samsung 840 EVO 120GB 2.5" Solid State Drive (£54.97 @ CCL Computers)
Video Card: Sapphire Radeon R7 260X 2GB Video Card (£79.99 @ Amazon UK)
Case: Corsair 200R ATX Mid Tower Case (£43.19 @ Aria PC)...
This'd suit your needs best:

PCPartPicker part list / Price breakdown by merchant

CPU: AMD FX-8320 3.5GHz 8-Core Processor (£97.99 @ Aria PC)
CPU Cooler: Cooler Master Hyper 212 EVO 82.9 CFM Sleeve Bearing CPU Cooler (£24.86 @ CCL Computers)
Motherboard: Asus M5A97 R2.0 ATX AM3+ Motherboard (£63.56 @ Scan.co.uk)
Memory: G.Skill Ripjaws X Series 8GB (2 x 4GB) DDR3-2133 Memory (£72.30 @ Amazon UK)
Storage: Samsung 840 EVO 120GB 2.5" Solid State Drive (£54.97 @ CCL Computers)
Video Card: Sapphire Radeon R7 260X 2GB Video Card (£79.99 @ Amazon UK)
Case: Corsair 200R ATX Mid Tower Case (£43.19 @ Aria PC)
Power Supply: EVGA 600B 600W 80+ Bronze Certified ATX Power Supply (£45.12 @ Scan.co.uk)
Optical Drive: Samsung SH-224DB/BEBE DVD/CD Writer (£10.22 @ CCL Computers)
Operating System: Microsoft Windows 7 Professional SP1 (OEM) (64-bit) (£44.95 @ Amazon UK)
Total: £537.15
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2014-09-01 18:59 BST+0100

The DVD burning/editing/rendering would require better multi core performance so included a FX 8 with OCable MoBo and cooler for better overall performance. Included 2133MHz sticks as rendering requires fast memory and that's why included 120GB SSD, you can add a 1TB HDD for 35 bucks later, when you feel the space is running out. A reasonable PSU and case to compliment it with a fairly powerful card for medium-high gaming :)
 
Solution