Wrong version for your OS
Dreamweaver Ver. 8 (a.k.a. 2005) requires Win 2K\XP.
Dreamweaver MX 2004 (a.k.a. 2003) will run on Win98SE and up.
Below are system requirements for various versions of Dreamweaver:
The following sections list the hardware and operating system requirements for specific versions of Dreamweaver running on the Microsoft Windows platform. The approximate release year of each software version is listed after the version name in parentheses.
QUOTE
Dreamweaver 8 (2005)
800 MHz Intel Pentium III processor (or equivalent) and later
Windows 2000, Windows XP
256 MB RAM (1 GB recommended to run more than one Studio 8 product simultaneously)
1024 x 768, 16-bit display (32-bit recommended)
650 MB available disk space
Dreamweaver MX 2004 (2003)
600 MHz Intel Pentium III processor or equivalent
Windows 98 SE (4.10.2222 A), Windows 2000, or Windows XP
128 MB RAM (256 MB recommended)
275 MB available disk space
Dreamweaver MX (2002)
Intel Pentium II processor or equivalent, 300 MHz or faster
Windows 98, 2000, NT (with Service Pack 3 or later), ME or XP
version 4.0 or later of Netscape Navigator or Microsoft Internet Explorer
96 MB RAM (128 MB recommended)
275 MB available disk space
monitor capable of 800 x 600 pixel resolution (millions of colors and 1024 x 768 pixel resolution recommended)
CD-ROM drive
Dreamweaver 4 and Dreamweaver UltraDev 4 (2000)
Intel Pentium processor or equivalent, 166 MHz or faster
Windows 95, 98, ME, 2000, NT 4 (with Service Pack 5), XP
version 4.0 or later of Netscape Navigator or Microsoft Internet Explorer
32 MB RAM (64 MB RAM for UltraDev)
110 MB available disk space (170 MB for UltraDev)
256-color monitor capable of 800 x 600 pixel resolution
CD-ROM drive
Macromedia Flash Player to view the Guided Tours and Lessons
Dreamweaver UltraDev 1 (2000)
Intel Pentium processor or equivalent, 166 MHz or faster
Windows 95, 98, ME, 2000, NT 4 (with Service Pack 5)
48 MB RAM
30 MB available disk space
Microsoft Data Access Components (MDAC) 2.1
if using JDBC, Sun's Java Development Kit version 1.1.8
Macromedia Shockwave 8 to view the Guided Tours and Show Me movies
256-color monitor capable of 800 x 600 pixel resolution
CD-ROM drive
Dreamweaver 3 (1999)
Intel Pentium processor or equivalent, 120 MHz or faster
Windows 95, 98, ME, 2000, or NT 4
32 MB RAM
20 MB available disk space
color monitor capable of 800 x 600 pixel resolution
CD-ROM drive
Dreamweaver 2 (1998)
Intel Pentium 90 processor or equivalent
Windows 95, 98, or NT 4
16 MB RAM
20 MB available disk space
color monitor capable of 800 x 600 pixel resolution
CD-ROM drive
Dreamweaver 1 (1997)
Intel Pentium 90 processor or equivalent
Windows 95 or NT 3
16 MB RAM
20 MB available disk space
color monitor
CD-ROM drive