OK, have it another shot this evening. Now it crashed when trying to play a 10 second avi (HUFF). Here's the error:

Sony Vegas 6.0 TRIAL
Version 6.0a (Build 99)
Exception 0xC0000005 (access violation) READ:0x44C IP:0x6435B6
In Module 'vegas60.exe' at Address 0x400000 + 0x2435B6
Thread: VideoRender ID=0x818 Stack=0x13BAF000-0x13BB0000
Registers:
EAX=00000000 CS=001b EIP=006435b6 EFLGS=00010246
EBX=0000001c SS=0023 ESP=13bafbf0 EBP=001fad90
ECX=00000000 DS=0023 ESI=00000000 FS=003b
EDX=001fad9c ES=0023 EDI=58514ef0 GS=0000
Bytes at CS:EIP:
006435B6: 8B 81 4C 04 00 00 74 1D ..L...t.
006435BE: 85 C0 75 17 0F B7 41 12 ..u...A.
Stack Dump:
13BAFBF0: 0065A6A9 00400000 + 25A6A9 (vegas60.exe)
13BAFBF4: 00000000
13BAFBF8: 008DA118 00400000 + 4DA118 (vegas60.exe)
13BAFBFC: 00000003
13BAFC00: 00000000
13BAFC04: 58514EF0 58430000 + E4EF0
13BAFC08: 00000000
13BAFC0C: 58514EE8 58430000 + E4EE8
13BAFC10: 00000000
13BAFC14: 00000000
13BAFC18: 00000000
13BAFC1C: 0000001C
13BAFC20: 0065AF06 00400000 + 25AF06 (vegas60.exe)
13BAFC24: 13D440B0 13CB0000 + 940B0
13BAFC28: 0015D280 00140000 + 1D280
13BAFC2C: 58514EF0 58430000 + E4EF0
> 13BAFCA8: 00650909 00400000 + 250909 (vegas60.exe)
13BAFCAC: 001FAD90 00140000 + BAD90
13BAFCB0: 13D440B0 13CB0000 + 940B0
13BAFCB4: 0015D280 00140000 + 1D280
13BAFCB8: 00000000
> 13BAFCD4: 00651846 00400000 + 251846 (vegas60.exe)
13BAFCD8: 58514EE0 58430000 + E4EE0
13BAFCDC: 001FAD90 00140000 + BAD90
13BAFCE0: 58575E38 58430000 + 145E38
13BAFCE4: 00000000
> 13BAFCEC: 006517F8 00400000 + 2517F8 (vegas60.exe)
- - -
13BAFFF0: 00000000
13BAFFF4: 00570850 00400000 + 170850 (vegas60.exe)
13BAFFF8: 00179670 00140000 + 39670
13BAFFFC: 00000000

I can't work in Vegas for longer than 5 mintues without it tanking---what gives?!