If I am reading this right, you want to comb the logs for entries between 5PM and 10PM each night from Monday to Friday. For this I would use Get-EventLog like you started to do. This script will iterate from the start date specified for 5 days and pull the logs as described by the filters from 5PM to 10PM each day. It also adds a LogFile element to each item to state if it came from the System or Applications log.
$StartDate = Get-Date "2/5/14"
$TargetComputer = "BP1XEUTS399"
$Logs = @()
For($i=0;$i -lt 5;$i++){
$TargetDate = $StartDate.AddDays($i)
$From = $TargetDate.AddHours(17)
$To = $From.AddHours(5)
#Remember what Error Actions is currently set to, and then set it to silent to avoid errors thrown when no log entries are found due to filters
$CurErrAct = $ErrorActionPreference
$ErrorActionPreference = "SilentlyContinue"
$Sys = Get-EventLog -Log System -After $From -Before $To -Source "Srv"
$Sys|%{$_|Add-Member -MemberType NoteProperty -Name "LogFile" -Value "System"}
$Apps = Get-EventLog -Log Application -ComputerName $TargetComputer -After $From -Before $To -EntryType Error,Warning
$Apps|%{$_|Add-Member -MemberType NoteProperty -Name "LogFile" -Value "Applications"}
$Logs += $Sys
$Logs += $Apps
#Set Error Actions back to what it was.
$ErrorActionPreference = $CurErrAct
}
$Logs|FT -autosize LogFile,EntryType,Source,Message
A couple notes, I replicated what you had in your question as closely as I could, so the System log being pulled is the local System log. The Applications log is on a remote computer. If you want to pull the System log on the same computer add -ComputerName $TargetComputer
to the $Sys = Get-EventLog
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