Here is a sample MXM.XML for you to use. change the network stuff to suit your setup or remove it if you dont need it.
<Config>
<Main>
<MenuPath>c:\</MenuPath>
<skinspath>c:\skins</skinspath>
</Main>
<Network>
<UseDHCP>False</UseDHCP>
<IP>192.168.1.200</IP>
<DefaultGateway>192.168.1.1</DefaultGateway>
<SubnetMask>255.255.255.0</SubnetMask>
<DNS1>192.168.1.1</DNS1>
<DNS2>24.94.63.33</DNS2>
</Network>
<FTPServer>
<ServerPort>21</ServerPort>
<username>xbox</username>
<password>xbox</password>
<AllowAnon>False</AllowAnon>
<AnonRoot>/</AnonRoot>
</FTPServer>
</Config>
Here is a sample Menu.XML
<Menu>
<Item>
<Title>Xbox Media Player</Title>
<Description>Music, Videos, Pictures</Description>
<Media>F:\apps\xbplayer\MXM_SS.WMV</Media>
<Exe>F:\apps\xbplayer\default.xbe</Exe>
</Item>
<Submenu>
<SortField>Title</SortField>
<Title>Applications</Title>
<Media>F:\apps\MXM_SS.WMV</Media>
<Item>
<AutoDir Flatten="true" Recurse="true">E:\apps\</AutoDir>
</Item>
<Item>
<AutoDir Flatten="true" Recurse="true">F:\apps\</AutoDir>
</Item>
</Submenu>
<Submenu>
<SortField>Title</SortField>
<Title>Games</Title>
<Media>F:\games\MXM_SS.WMV</Media>
<Item>
<AutoDir Flatten="true" Recurse="true">E:\games\</AutoDir>
</Item>
<Item>
<AutoDir Flatten="true" Recurse="true">F:\games\</AutoDir>
</Item>
</Submenu>
<Submenu>
<SortField>Title</SortField>
<Title>Emulators</Title>
<Media>F:\games_emu\MXM_SS.WMV</Media>
<Item>
<AutoDir Flatten="true" Recurse="true">F:\games_emu\</AutoDir>
</Item>
</Submenu>
<Submenu>
<SortField>Title</SortField>
<Title>DashBoards</Title>
<Media>F:\dashboard\MXM_SS.WMV</Media>
<Item>
<Title>MS</Title>
<Description>Original Dashboard</Description>
<Exe>C:\xboxdash.xbe</Exe>
<Media>C:\MXM_SS.WMV</Media>
</Item>
<Item>
<Title>EvoX</Title>
<Description>Original Mod Dashboard</Description>
<Exe>F:\dashboardevox\default.xbe</Exe>
<Media>F:\dashboardevox\MXM_SS.WMV</Media>
</Item>
<Item>
<Title>AvaLaunch</Title>
<Description>upcoming Dash</Description>
<Exe>F:\dashboardavalaunch\default.xbe</Exe>
<Media>F:\dashboardavalaunch\MXM_SS.WMV</Media>
</Item>
</Submenu>
</Menu>
Hope it helps you out.