I think this would be a great mod portable yet powerful and i think will fit in the $500.00 limit here are the components

1. ion board free

2. memory free

3. 120 GB ssd free

4. operating system free

5. ASUS VH242H Black 23.6" 5ms HDMI Full 1080P Widescreen LCD Monitor 300 cd/m2 1000:1 (ASCR 20000:1) Built in Speakers newegg $199.00

6. LITE-ON Black 8X DVD+R 8X DVD+RW 8X DVD-R 6X DVD-RW 5X DVD-RAM 8X DVD-ROM 24X CD-R 24X CD-RW 24X CD-ROM 2MB Cache SATA Slot Load Slim CD/DVD Burner - OEM newegg $49.99

7. Linkworld 82001B-28FU+P81 black/silver Steel Mini-ITX Tower Computer Case 65W external adaptor power Power Supply newegg $75.99

8. plexiglass parts for the stand and back cover and door less than $100.00

9. shipping on parts 5-7 from newegg is 15.68

here are some rough drawings of the layout